The cardiovascular system consists of the heart and blood vessels. The heart has four chambers - the right and left atria receive blood, and the right and left ventricles pump blood out. Blood flows through arteries, capillaries, and veins in a closed circuit. The heart is a muscular pump made of cardiac muscle that is located in the chest cavity. It is surrounded by membranes and tissues that protect it. Valves ensure blood flows in only one direction through the heart and vessels.
The lymphatic system transports lymph fluid and filters pathogens. It includes lymph vessels, lymph nodes, the spleen, thymus, tonsils, and bone marrow. Lymph fluid contains lymphocytes and drains excess tissue fluid, absorbed fats, and cell debris from tissues. It transports these materials through lymph vessels and lymph nodes which filter the lymph. The spleen, thymus and tonsils are lymphatic organs that help produce and store lymphocytes to fight infection. The document describes the structures and functions of the lymphatic system components in detail.
The respiratory system exchanges gases through a series of organs. The document describes the key parts and functions of the respiratory system. It focuses on the nose, which warms, moistens, and filters air before it reaches the lungs. It then describes the pharynx and larynx, which continue guiding air through the upper respiratory tract. The larynx contains cartilages like the thyroid and cricoid that support vocal cord function and air passage.
This document provides an overview of the cardiovascular system and its histology. It begins with objectives of describing the histological features of the heart and blood vessels. It then introduces the cardiovascular system and describes the histological features of the heart's three layers - epicardium, myocardium, and endocardium. It also discusses the histology of blood vessels, including the layers of the vessel wall and differences between arteries, veins, and capillaries. Finally, it discusses some clinical applications regarding diseases that impact the cardiovascular system histology.
The lymphatic system consists of lymph vessels, lymph nodes, and lymph that work together to transport fluid and defend the body against disease. Lymph is a fluid containing white blood cells that flows through lymph vessels and lymph nodes, where the nodes filter out pathogens and foreign materials. The lymph eventually drains into the bloodstream via two main ducts. Disorders can occur if the lymphatic system becomes blocked or infected, impairing its ability to circulate lymph and mount an immune response.
cardiovascular system
blood vessels
biology
b.pharma
Introduction to Heart
Location & position of heart
Anatomy of heart
Heart wall
Valves of heart
Heart – Interior of front
Lymphatic Drainage of Head and Neck. Includes Introduction to the lymphatic system, embryology, classification, anatomy, palpation and various disorders of the lymphatic system.
The urinary system consists of the kidneys, ureters, bladder, and urethra. The kidneys filter the blood and remove waste, which is transported through the ureters to the bladder. The bladder stores urine until it is released through the urethra. Key functions include filtering waste from the blood and maintaining water and electrolyte balance. The kidneys receive blood from the renal arteries and produce urine that is collected in the renal pelvis before exiting through the ureters.
The urinary system consists of the kidneys, ureters, urinary bladder, and urethra. The kidneys filter waste from the blood in the form of urine, which travels through the ureters to the bladder. The bladder stores urine until urination, when it is expelled through the urethra. The kidneys contain nephrons, which filter the blood and reabsorb necessary substances, producing urine that is collected and excreted.
The lymphatic system transports lymph fluid and filters pathogens. It includes lymph vessels, lymph nodes, the spleen, thymus, tonsils, and bone marrow. Lymph fluid contains lymphocytes and drains excess tissue fluid, absorbed fats, and cell debris from tissues. It transports these materials through lymph vessels and lymph nodes which filter the lymph. The spleen, thymus and tonsils are lymphatic organs that help produce and store lymphocytes to fight infection. The document describes the structures and functions of the lymphatic system components in detail.
The respiratory system exchanges gases through a series of organs. The document describes the key parts and functions of the respiratory system. It focuses on the nose, which warms, moistens, and filters air before it reaches the lungs. It then describes the pharynx and larynx, which continue guiding air through the upper respiratory tract. The larynx contains cartilages like the thyroid and cricoid that support vocal cord function and air passage.
This document provides an overview of the cardiovascular system and its histology. It begins with objectives of describing the histological features of the heart and blood vessels. It then introduces the cardiovascular system and describes the histological features of the heart's three layers - epicardium, myocardium, and endocardium. It also discusses the histology of blood vessels, including the layers of the vessel wall and differences between arteries, veins, and capillaries. Finally, it discusses some clinical applications regarding diseases that impact the cardiovascular system histology.
The lymphatic system consists of lymph vessels, lymph nodes, and lymph that work together to transport fluid and defend the body against disease. Lymph is a fluid containing white blood cells that flows through lymph vessels and lymph nodes, where the nodes filter out pathogens and foreign materials. The lymph eventually drains into the bloodstream via two main ducts. Disorders can occur if the lymphatic system becomes blocked or infected, impairing its ability to circulate lymph and mount an immune response.
cardiovascular system
blood vessels
biology
b.pharma
Introduction to Heart
Location & position of heart
Anatomy of heart
Heart wall
Valves of heart
Heart – Interior of front
Lymphatic Drainage of Head and Neck. Includes Introduction to the lymphatic system, embryology, classification, anatomy, palpation and various disorders of the lymphatic system.
The urinary system consists of the kidneys, ureters, bladder, and urethra. The kidneys filter the blood and remove waste, which is transported through the ureters to the bladder. The bladder stores urine until it is released through the urethra. Key functions include filtering waste from the blood and maintaining water and electrolyte balance. The kidneys receive blood from the renal arteries and produce urine that is collected in the renal pelvis before exiting through the ureters.
The urinary system consists of the kidneys, ureters, urinary bladder, and urethra. The kidneys filter waste from the blood in the form of urine, which travels through the ureters to the bladder. The bladder stores urine until urination, when it is expelled through the urethra. The kidneys contain nephrons, which filter the blood and reabsorb necessary substances, producing urine that is collected and excreted.
The lymphatic system works with the cardiovascular system to return fluid to the bloodstream that has escaped into tissues. Lymph is tissue fluid that is picked up by lymph capillaries from interstitial fluid and contains oxygen, proteins, glucose and white blood cells. Lymph vessels carry lymph through lymph nodes which filter the lymph before returning it to the bloodstream via the thoracic duct or right lymphatic duct. Key components of the lymphatic system include lymph nodes, tonsils, spleen and thymus which help fight infection and return fluid to circulation.
The male reproductive system includes internal structures like the testes, epididymis, ductus deferens, seminal vesicles, prostate, and penis. The testes are held in the scrotum and produce sperm. Sperm travel through the epididymis, ductus deferens, and ejaculatory duct before mixing with fluids from the seminal vesicles and prostate to form semen, which is ejaculated through the urethra in the penis during orgasm. Blood flows into the structures via internal iliac arteries and drains via internal iliac veins. Lymphatic drainage is to internal and external iliac lymph nodes.
The kidneys filter blood to produce urine and are located between vertebrae T12-L3. Each kidney contains an outer cortex where filtering occurs and an inner medulla composed of renal pyramids. Blood enters the kidneys through the renal artery and leaves through the renal vein, undergoing filtration in structures called nephrons. Urine flows from nephrons through collecting ducts into minor calyces, major calyces, the renal pelvis, ureters, bladder, and urethra to exit the body. The ureters are muscular tubes that carry urine from kidneys to bladder. The bladder is a muscular reservoir organ where urine is stored before exiting through the urethra.
This document provides an overview of the anatomy and physiology of the urinary system. It describes the key components - kidneys, ureters, bladder, and urethra. It discusses the internal anatomy of the kidneys including the cortex, medulla, nephrons, and blood supply. It also summarizes kidney functions like filtration, reabsorption, and regulation of water, electrolytes and acid-base balance. Physiological concepts like glomerular filtration rate and the mechanisms of filtration and tubular transport are explained as well.
1. The document describes the anatomy and features of the jejunum, ileum, and large intestine.
2. Key differences between the jejunum and ileum are described, including their location in the abdomen and structural characteristics.
3. The large intestine is then described, including sections like the cecum, appendix, ascending colon, and their blood supply.
The kidneys are paired organs located in the abdominal cavity. Each kidney has an outer renal cortex and inner renal medulla. Within these regions are over 1 million microscopic filtration units called nephrons. Nephrons contain a renal corpuscle for blood filtration and a renal tubule for fluid processing. Processed fluid drains into collecting ducts and exits the kidneys as urine through the ureters. The kidneys are supplied with blood from the renal arteries and are surrounded by protective layers of tissue.
The lymphatic system consists of lymph vessels, lymph nodes, and lymphoid tissues that work together to drain excess fluid from tissues, absorb and transport fatty acids from the gut, and help fight infection. Lymph is formed when interstitial fluid drains into initial lymphatic vessels and circulates through a network of vessels, nodes, ducts, and eventually returns to the bloodstream. Lymph nodes filter lymph as it circulates and contain immune cells that help fight pathogens. The major lymphatic ducts are the thoracic duct and right lymphatic duct which drain lymph into the bloodstream in the neck.
The urinary system consists of the kidneys, ureters, urinary bladder, and urethra. The kidneys filter waste from the blood and regulate fluid and electrolyte balance. Urine travels from the kidneys down the ureters into the muscular urinary bladder, which stores urine until emptying through the urethra. The urinary system works to eliminate waste from the body and maintain homeostasis.
Anatomy and physiology of male reproductive systemPallavi Lokhande
The organs of the male reproductive system include the testes, a system of ducts (including the epididymis, ductus deferens, ejaculatory ducts, and urethra), accessory sex glands (seminal vesicles, prostate, and bulbourethral glands), and several supporting Structures, including the scrotum and the penis.
and knowledge of this system can help in knowing abnormality in it as well as can be used as study material
The urinary system develops through three successive phases - the pronephros, mesonephros, and metanephros. The pronephros is nonfunctional in mammals. The mesonephros allows for filtration of blood into mesonephric tubules. During the fifth week of gestation, the ureteric bud induces nearby mesoderm to form the metanephros, or permanent kidneys. The kidneys filter waste from the blood to form urine, which drains via the ureters into the bladder and is then excreted through the urethra. The basic functional unit of the kidneys is the nephron, which filters the blood and reabsorbs necessary molecules
Anatomy and physiology of the Urinary system by Dipali HarkhaniDipali Harkhani
The document summarizes the anatomy and physiology of the urinary system. It describes the main components of the urinary system as the kidneys, ureters, bladder, and urethra. The kidneys filter waste from the blood to produce urine, which travels through the ureters to the bladder. The bladder stores urine until urination, when urine exits through the urethra. The nephron is the functional unit of the kidney that filters blood and modifies it into urine through processes of filtration, reabsorption, and secretion.
The cardiovascular system consists of the heart and blood vessels. The heart has four chambers and pumps blood through the blood vessels. It is surrounded by layers including the outer fibrous pericardium, middle myocardial muscle layer, and inner endocardial lining. Blood flows from the heart through arteries and arterioles, into capillaries where gas exchange occurs, and returns to the heart through veins and venules. Valves in the heart and vessels ensure one-way blood flow. The cardiovascular system circulates blood to supply the body with oxygen and nutrients and remove waste.
The lymphatic system consists of lymph, lymphatic vessels, lymphatic tissue, and lymphatic organs. Lymph is a clear fluid that transports tissue fluid, lymphocytes, bacteria, and cancer cells through lymphatic vessels and capillaries. The vessels converge in lymph nodes before draining into the subclavian veins. Primary lymphatic organs are the red bone marrow and thymus, which produce lymphocytes. Secondary lymphatic organs include lymph nodes, tonsils, spleen, Peyer's patches, and appendix, which filter lymph and mount immune responses.
The urinary system removes waste from the bloodstream through the kidneys, which filter blood to form urine. The urine travels from the kidneys to the bladder via ureters. The bladder stores urine until urination, when urine exits the body through the urethra. The kidneys contain nephrons, which filter blood in the glomerulus and reabsorb nutrients in the tubules, forming urine.
The lymphatic system filters and returns fluid from tissues to the bloodstream. It consists of lymphatic vessels, lymph nodes, and lymphoid tissues like the spleen and thymus gland. The lymphatic system helps fight infection through lymphocytes and transports fatty acids from the intestines via the lacteals. It is important for fluid balance as excess interstitial fluid is otherwise cause edema if not returned to the bloodstream by the lymphatic vessels.
The document summarizes the lymphatic drainage of major organs. It describes how the lymphatic vessels from the gastrointestinal tract drain into lymph nodes along blood vessels and ultimately into the cisterna chyli and thoracic duct. It also outlines the lymphatic drainage patterns of the liver, spleen, male and female genital tracts, and mediastinum.
The circulatory system transports fluids throughout the body;
it consists of the cardiovascular and lymphatic systems.
The heart and blood vessels make up the blood transportation network, the cardiovascular system.
Through this system, the heart pumps blood through the body’s vast system of blood vessels.
The blood carries nutrients, oxygen, and waste products to and from the cells.
VASCULAR CIRCUITS
The heart consists of two muscular pumps dividing the circulation into two components:
pulmonary circulations
systemic circulations or circuit
Pulmonary Circulation
Rt ventricle propels low O2 blood into the lungs via the pulmonary arteries.
CO2 is exchanged for O2 in the capillaries of the lungs.
Then the O2 -rich blood is returned via the pulmonary veins to the Lft atrium.
This circuit, from the right ventricle through the lungs to the left atrium, is the pulmonary circulation.
Systemic Circulation
Left ventricle propels the O2 -rich blood through systemic arteries (the aorta and its branches),
exchanging O2 and nutrients for CO2 in the remainder of the body’s capillaries.
Low- O2 blood returns to right atrium via systemic veins (tributaries of the superior and inferior vena cava).
This circuit, from left ventricle to right atrium, is the systemic circulation.
The lymphatic system works with the cardiovascular system to return fluid to the bloodstream that has escaped into tissues. Lymph is tissue fluid that is picked up by lymph capillaries from interstitial fluid and contains oxygen, proteins, glucose and white blood cells. Lymph vessels carry lymph through lymph nodes which filter the lymph before returning it to the bloodstream via the thoracic duct or right lymphatic duct. Key components of the lymphatic system include lymph nodes, tonsils, spleen and thymus which help fight infection and return fluid to circulation.
The male reproductive system includes internal structures like the testes, epididymis, ductus deferens, seminal vesicles, prostate, and penis. The testes are held in the scrotum and produce sperm. Sperm travel through the epididymis, ductus deferens, and ejaculatory duct before mixing with fluids from the seminal vesicles and prostate to form semen, which is ejaculated through the urethra in the penis during orgasm. Blood flows into the structures via internal iliac arteries and drains via internal iliac veins. Lymphatic drainage is to internal and external iliac lymph nodes.
The kidneys filter blood to produce urine and are located between vertebrae T12-L3. Each kidney contains an outer cortex where filtering occurs and an inner medulla composed of renal pyramids. Blood enters the kidneys through the renal artery and leaves through the renal vein, undergoing filtration in structures called nephrons. Urine flows from nephrons through collecting ducts into minor calyces, major calyces, the renal pelvis, ureters, bladder, and urethra to exit the body. The ureters are muscular tubes that carry urine from kidneys to bladder. The bladder is a muscular reservoir organ where urine is stored before exiting through the urethra.
This document provides an overview of the anatomy and physiology of the urinary system. It describes the key components - kidneys, ureters, bladder, and urethra. It discusses the internal anatomy of the kidneys including the cortex, medulla, nephrons, and blood supply. It also summarizes kidney functions like filtration, reabsorption, and regulation of water, electrolytes and acid-base balance. Physiological concepts like glomerular filtration rate and the mechanisms of filtration and tubular transport are explained as well.
1. The document describes the anatomy and features of the jejunum, ileum, and large intestine.
2. Key differences between the jejunum and ileum are described, including their location in the abdomen and structural characteristics.
3. The large intestine is then described, including sections like the cecum, appendix, ascending colon, and their blood supply.
The kidneys are paired organs located in the abdominal cavity. Each kidney has an outer renal cortex and inner renal medulla. Within these regions are over 1 million microscopic filtration units called nephrons. Nephrons contain a renal corpuscle for blood filtration and a renal tubule for fluid processing. Processed fluid drains into collecting ducts and exits the kidneys as urine through the ureters. The kidneys are supplied with blood from the renal arteries and are surrounded by protective layers of tissue.
The lymphatic system consists of lymph vessels, lymph nodes, and lymphoid tissues that work together to drain excess fluid from tissues, absorb and transport fatty acids from the gut, and help fight infection. Lymph is formed when interstitial fluid drains into initial lymphatic vessels and circulates through a network of vessels, nodes, ducts, and eventually returns to the bloodstream. Lymph nodes filter lymph as it circulates and contain immune cells that help fight pathogens. The major lymphatic ducts are the thoracic duct and right lymphatic duct which drain lymph into the bloodstream in the neck.
The urinary system consists of the kidneys, ureters, urinary bladder, and urethra. The kidneys filter waste from the blood and regulate fluid and electrolyte balance. Urine travels from the kidneys down the ureters into the muscular urinary bladder, which stores urine until emptying through the urethra. The urinary system works to eliminate waste from the body and maintain homeostasis.
Anatomy and physiology of male reproductive systemPallavi Lokhande
The organs of the male reproductive system include the testes, a system of ducts (including the epididymis, ductus deferens, ejaculatory ducts, and urethra), accessory sex glands (seminal vesicles, prostate, and bulbourethral glands), and several supporting Structures, including the scrotum and the penis.
and knowledge of this system can help in knowing abnormality in it as well as can be used as study material
The urinary system develops through three successive phases - the pronephros, mesonephros, and metanephros. The pronephros is nonfunctional in mammals. The mesonephros allows for filtration of blood into mesonephric tubules. During the fifth week of gestation, the ureteric bud induces nearby mesoderm to form the metanephros, or permanent kidneys. The kidneys filter waste from the blood to form urine, which drains via the ureters into the bladder and is then excreted through the urethra. The basic functional unit of the kidneys is the nephron, which filters the blood and reabsorbs necessary molecules
Anatomy and physiology of the Urinary system by Dipali HarkhaniDipali Harkhani
The document summarizes the anatomy and physiology of the urinary system. It describes the main components of the urinary system as the kidneys, ureters, bladder, and urethra. The kidneys filter waste from the blood to produce urine, which travels through the ureters to the bladder. The bladder stores urine until urination, when urine exits through the urethra. The nephron is the functional unit of the kidney that filters blood and modifies it into urine through processes of filtration, reabsorption, and secretion.
The cardiovascular system consists of the heart and blood vessels. The heart has four chambers and pumps blood through the blood vessels. It is surrounded by layers including the outer fibrous pericardium, middle myocardial muscle layer, and inner endocardial lining. Blood flows from the heart through arteries and arterioles, into capillaries where gas exchange occurs, and returns to the heart through veins and venules. Valves in the heart and vessels ensure one-way blood flow. The cardiovascular system circulates blood to supply the body with oxygen and nutrients and remove waste.
The lymphatic system consists of lymph, lymphatic vessels, lymphatic tissue, and lymphatic organs. Lymph is a clear fluid that transports tissue fluid, lymphocytes, bacteria, and cancer cells through lymphatic vessels and capillaries. The vessels converge in lymph nodes before draining into the subclavian veins. Primary lymphatic organs are the red bone marrow and thymus, which produce lymphocytes. Secondary lymphatic organs include lymph nodes, tonsils, spleen, Peyer's patches, and appendix, which filter lymph and mount immune responses.
The urinary system removes waste from the bloodstream through the kidneys, which filter blood to form urine. The urine travels from the kidneys to the bladder via ureters. The bladder stores urine until urination, when urine exits the body through the urethra. The kidneys contain nephrons, which filter blood in the glomerulus and reabsorb nutrients in the tubules, forming urine.
The lymphatic system filters and returns fluid from tissues to the bloodstream. It consists of lymphatic vessels, lymph nodes, and lymphoid tissues like the spleen and thymus gland. The lymphatic system helps fight infection through lymphocytes and transports fatty acids from the intestines via the lacteals. It is important for fluid balance as excess interstitial fluid is otherwise cause edema if not returned to the bloodstream by the lymphatic vessels.
The document summarizes the lymphatic drainage of major organs. It describes how the lymphatic vessels from the gastrointestinal tract drain into lymph nodes along blood vessels and ultimately into the cisterna chyli and thoracic duct. It also outlines the lymphatic drainage patterns of the liver, spleen, male and female genital tracts, and mediastinum.
The circulatory system transports fluids throughout the body;
it consists of the cardiovascular and lymphatic systems.
The heart and blood vessels make up the blood transportation network, the cardiovascular system.
Through this system, the heart pumps blood through the body’s vast system of blood vessels.
The blood carries nutrients, oxygen, and waste products to and from the cells.
VASCULAR CIRCUITS
The heart consists of two muscular pumps dividing the circulation into two components:
pulmonary circulations
systemic circulations or circuit
Pulmonary Circulation
Rt ventricle propels low O2 blood into the lungs via the pulmonary arteries.
CO2 is exchanged for O2 in the capillaries of the lungs.
Then the O2 -rich blood is returned via the pulmonary veins to the Lft atrium.
This circuit, from the right ventricle through the lungs to the left atrium, is the pulmonary circulation.
Systemic Circulation
Left ventricle propels the O2 -rich blood through systemic arteries (the aorta and its branches),
exchanging O2 and nutrients for CO2 in the remainder of the body’s capillaries.
Low- O2 blood returns to right atrium via systemic veins (tributaries of the superior and inferior vena cava).
This circuit, from left ventricle to right atrium, is the systemic circulation.
The document summarizes the cardiovascular system, focusing on blood vessels. There are five main types of blood vessels - arteries, arterioles, capillaries, venules and veins. Arteries carry oxygenated blood away from the heart, branching into smaller arterioles and then capillaries where gas and nutrient exchange occurs. Capillaries then join to form venules and veins to return deoxygenated blood back to the heart. Each vessel type has a distinct layered structure and role in regulating blood flow and pressure throughout the body.
Blood vessels carry blood throughout the body via different types of vessels - arteries, arterioles, capillaries, venules and veins. The main types of blood vessels are described including their structure, layers, role in circulation and factors that influence blood flow. Arteries carry blood away from the heart, veins carry blood back to the heart, and capillaries allow for exchange of oxygen, nutrients and waste between the blood and tissues. Proper circulation is maintained through vessel structure, autonomic control, and various pumping mechanisms.
Circulatory system of head and neck BY DR. C. P. ARYA (B.Sc. B.D.S.; M.D.S.;...DR. C. P. ARYA
The document discusses the circulatory system of the head and neck, including key arteries and structures:
- The common carotid artery divides into the external and internal carotid arteries, with the external supplying blood to the face and neck and the internal supplying the brain.
- Important structures along the carotid arteries include the carotid body, which detects changes in blood gases, and the carotid sinus, a baroreceptor site.
- Branches of the external carotid artery include the superior thyroid artery and branches that supply the face and pharynx. The internal carotid artery branches further within the skull to supply the brain.
The document discusses the structure and function of blood vessels in the human body. It describes the three layers that make up the walls of arteries, and explains how arteries carry oxygenated blood away from the heart to tissues. It then discusses how blood flows from arteries into capillaries, where gas exchange occurs, and then into veins which carry deoxygenated blood back to the heart. Several factors that aid the circulation of blood in veins are also listed.
The circulatory system transports blood from the heart to the body and back again through a closed tubular network of arteries, veins, and capillaries. Arteries carry oxygenated blood away from the heart while veins carry deoxygenated blood back to the heart. Capillaries connect the arteries and veins and facilitate the exchange of water, oxygen, carbon dioxide, nutrients and waste. The structure of blood vessels enables them to perform their unique functions in circulation and regulation of blood flow.
Blood Vessels
By: Saiyed Falakaara
Assistant Professor
Department of Pharmacy
Sumandeep Vidyapeeth
Introduction
Blood vessels form a closed system of tubes that carry blood away from the heart, transport it to the tissues of the body, and then return it to the heart.
The blood vessels of human body carry blood to every tissue and organ.
Vessels decrease in size as they move away from the heart (arteries and arterioles), ending in the capillaries, and then increase in size as they move towards the heart (venules and veins)
The largest artery in the blood is Aorta.
Types of blood vessels
1. Arteries
2. Arterioles
3. Capillaries
4. Venules
5. veins
The document discusses the structure of blood vessels, including the three layers - tunica interna, tunica media, and tunica externa. It describes the key components of each layer and how they vary across the different types of blood vessels - arteries, arterioles, capillaries, venules and veins. The structures are adapted to facilitate the transport and exchange of blood, nutrients and waste throughout the body.
The first topic in the practical histology coarse for pharmacy students
In this lecture the student will be able to recognize the histological layers of the circulatory system parts such as veins and arteries and the similarities and differences between each layer
The circulatory system, also known as the cardiovascular system, moves substances to and from cells and helps regulate body temperature and pH. It consists of the heart, blood, and blood vessels. The heart begins beating around 21 days after conception at a rate near the mother's, which then accelerates over the first month. Blood vessels include arteries, which carry blood away from the heart, veins, which carry blood toward the heart, and capillaries, which connect arterioles and venules and closely interact with tissues. Deoxygenated blood returns to the heart through the superior and inferior vena cavae and is pumped through the pulmonary and systemic circuits to be oxygenated in the lungs before being distributed to the body
The document summarizes the cardiovascular system and its components. It describes the heart, arteries, veins, capillaries and their classifications. It discusses circulation patterns like systemic, pulmonary and portal circulation. It also covers topics like anastomoses, blood supply of arteries and veins, and clinical conditions like atherosclerosis and aneurysms.
The document summarizes the structure and function of blood vessels. It describes the three layers (tunics) that make up arteries and veins, as well as the single-layered endothelium of capillaries. It then compares different types of blood vessels, including elastic and muscular arteries, arterioles, venules and veins. It discusses the roles of each in conducting blood away from the heart in arteries and returning it to the heart in veins. It also describes the structure of capillaries and their role in exchanging materials with tissues.
The cardiovascular system consists of the heart, arteries, veins, and capillaries. The heart pumps blood through arteries, which branch into smaller vessels and eventually capillaries where nutrients and waste are exchanged. Capillaries then drain into veins which collect blood and return it to the heart. The cardiovascular system transports blood throughout the body in two circuits - systemic circulation from the heart to the body and pulmonary circulation from the heart to the lungs.
The document summarizes the structure and function of the cardiovascular system. It describes the three main types of blood vessels - arteries, capillaries, and veins - and their roles in circulating blood throughout the body. Arteries carry oxygenated blood away from the heart, branching into smaller vessels. Capillaries allow for exchange of oxygen, nutrients, waste at the cellular level. Veins then collect deoxygenated blood and return it to the heart. The document provides detailed information on the layers, tissue composition, and regulatory mechanisms of different sections of the cardiovascular system.
The document discusses the anatomy and functions of the circulatory system. It describes the major components including blood, blood vessels, heart, and valves. The circulatory system transports oxygen, nutrients, wastes, hormones, and protects the body. It summarizes the types of blood vessels and capillaries. Arteries carry blood away from the heart while veins carry blood back to the heart. Capillaries allow for gas and nutrient exchange between blood and tissues. The document also provides details on the structure and chambers of the heart.
William Harvey was the first modern physiologist in the 16th century. He proved that blood circulates in a continuous loop from the heart to the arteries and back to the veins and heart, overturning the long-held Galenic view of two separate circulatory systems. The circulatory system consists of arteries, which carry blood away from the heart; capillaries, where gas and nutrient exchange occurs; and veins, which carry blood back to the heart. Arteries have thicker muscular walls than veins and carry oxygenated blood except in the pulmonary circulation.
The document summarizes the cardiovascular system, including:
1. The anatomy and physiology of the heart, including its chambers and layers. The heart pumps deoxygenated blood to the lungs and oxygenated blood to the body.
2. The three main types of blood circulation - pulmonary circulation between the heart and lungs, coronary circulation supplying the heart, and systemic circulation supplying the body. Blood vessels have three layers and blood flows through arteries, arterioles, capillaries and veins.
3. Key aspects of cardiac cycle including the phases of atrial and ventricular systole and diastole. Heart sounds and electrocardiograms are also summarized.
The document discusses the structure and function of the circulatory system. It describes the heart as a hollow muscular organ that pumps blood through arteries, capillaries, and veins. The heart has four chambers and a conduction system that generates electrical signals to coordinate contractions. Blood vessels branch throughout the body to deliver oxygen, nutrients and remove waste. Arteries carry blood away from the heart, veins carry blood back to the heart, and capillaries facilitate exchange of materials between blood and tissues.
1. The document discusses water, electrolyte, and pH balance in the human body. It describes the different fluid compartments, electrolyte composition and functions, acid-base balance, and mechanisms that regulate water and electrolyte levels.
2. Key points include that 60% of body weight is composed of water stored in intracellular and extracellular fluid compartments. Electrolytes like sodium, potassium, and chloride are important for fluid balance, nerve function, and pH regulation. The body maintains acid-base balance through buffer systems like bicarbonate and uses organs like the lungs and kidneys to regulate pH.
3. Imbalances can occur from dehydration, diarrhea, vomiting, or other causes and
Blood is a connective tissue composed of plasma and blood cells that circulates through the body delivering oxygen, nutrients, hormones and other substances to tissues. It transports waste products away from tissues. The main cellular components of blood are red blood cells, white blood cells and platelets. Red blood cells contain hemoglobin and transport oxygen and carbon dioxide. White blood cells help defend the body against infection and disease. Platelets assist in blood clotting. Disorders can occur if there are too few or too many blood cells or if the cells are abnormal.
The document discusses endocrine glands, specifically the endocrine gland. It defines endocrine glands as groups of secretory cells surrounded by an extensive network of capillaries that facilitates the diffusion of hormones directly into the bloodstream. Some key endocrine glands discussed include the pituitary gland, thyroid gland, and hypothalamus. The pituitary gland regulates other endocrine glands and is divided into the posterior and anterior pituitary. The hypothalamus produces hormones that regulate the anterior pituitary. The thyroid gland produces thyroid hormones that increase metabolism.
The document provides information about the digestive system, including the organs and processes involved. It describes the main parts of the digestive tract from mouth to anus. It details the layers of the digestive tract walls and explains the roles of the salivary glands, teeth, tongue, and liver and pancreas in digestion. Accessory organs help break down food while the stomach, small intestine, and large intestine further digest and absorb nutrients before waste is eliminated.
The muscular system provides motor power for all body movements through skeletal, smooth, and cardiac muscles. Skeletal muscles are voluntary striated muscles attached to bones by tendons that allow movement. Smooth muscles are involuntary and non-striated, found in organs. Cardiac muscle is exclusively in the heart. Each muscle fiber contains contractile myofilaments that slide past each other during contraction. Muscle contraction is stimulated by motor neurons at neuromuscular junctions. Contraction allows movement through pulling bones via tendons attached at muscle origins and insertions.
This document discusses the different types of joints in the human body. It begins by defining a joint and classifying joints by function and structure. The three main types by function are synarthrosis (immovable), amphiarthrosis (slightly movable), and diarthrosis (freely movable). The three main types by structure are fibrous, cartilaginous, and synovial joints. It then provides details on the different types of synovial joints and examples of various joints in the body like the shoulder, elbow, hip, knee, ankle joints. It concludes with a brief description of bursae and fontanels.
The integumentary system consists of the skin and its appendages. The skin is made up of two layers - the epidermis and dermis. The epidermis is avascular and composed of stratified squamous epithelium in five layers. The dermis lies below and contains blood vessels, hair follicles, and glands. Functions of the skin include protection, regulation of temperature and moisture, synthesis of vitamin D, and sensation. Sweat glands and sebaceous glands are important appendages that aid temperature regulation and protect the skin surface.
The skeletal system consists of bones and other connective tissues that provide structure and protect internal organs. Bones are composed of both organic and inorganic materials, including collagen proteins and hydroxyapatite salts. The skeletal system includes long bones in the limbs, short and flat bones, and irregular bones like those in the spine. Bones are living tissues that contain osteoblasts, osteocytes, and osteoclasts, which form, maintain, and break down bone respectively. The skeletal system provides structure, movement, protection, mineral storage, and blood cell formation.
This document discusses human growth and development from conception through adulthood. It defines growth as an increase in body size and weight, while development refers to the acquisition of skills and behaviors. The stages of development include prenatal (embryonic and fetal), infancy, childhood, adolescence, and adulthood. Prenatal development begins with fertilization and progresses through embryogenesis and fetal stages. After birth, development occurs through infancy, childhood, adolescence, and into adulthood. Nutrition, emotional support, and learning experiences influence growth and development at every stage of life.
The female reproductive system functions to produce eggs and hormones. It includes both external genital organs like the vulva and internal organs like the uterus, fallopian tubes, and ovaries. The ovaries produce eggs and hormones, the fallopian tubes help eggs reach the uterus, and the uterus supports pregnancy and childbirth. The system goes through monthly changes in a menstrual cycle regulated by hormones, culminating in ovulation when an egg is released for possible fertilization.
The male reproductive system consists of organs that produce and transfer mature sperm. The testes produce sperm which travel through the vas deferens, seminal vesicles and prostate gland. These organs combine their secretions to form semen, which contains sperm. During sexual arousal, erectile tissue in the penis fills with blood, causing an erection to allow delivery of semen into the female reproductive tract during intercourse.
Blood is composed of plasma and blood cells suspended in it. Plasma is 55% of blood volume and contains water, proteins, electrolytes, nutrients, waste products, hormones and gases. The three main types of blood cells are red blood cells (RBCs), white blood cells (WBCs) and platelets. RBCs contain hemoglobin and transport oxygen and carbon dioxide. WBCs help fight infection. Blood has many functions including nutrient and waste transport and immune function.
The document summarizes key information about endocrine glands and their hormones. It discusses that endocrine glands are groups of secretory cells that release hormones directly into the bloodstream. The major endocrine glands include the hypothalamus, pituitary gland, thyroid gland, parathyroid gland, adrenal gland, ovaries, testes, pancreas and pineal gland. Each gland secretes specific hormones that target distant tissues, regulating processes like growth, metabolism, reproduction and homeostasis. Hormone secretion is regulated by negative feedback loops between the hypothalamus and pituitary gland.
The document discusses the senses and sensory organs. It describes the five special senses - sight, smell, taste, touch, and hearing. It explains that sensory receptors convert stimuli into nerve impulses. The main sensory receptors are mechanoreceptors, chemoreceptors, photoreceptors, and thermoreceptors. Each sense organ contains specific receptors - for example, rods and cones in the eye and hair cells in the ear. The document then provides detailed descriptions of the eye, tongue, nose, skin and ear as sensory organs.
The peripheral nervous system (PNS) connects the central nervous system to the limbs and organs. It consists of 12 pairs of cranial nerves that originate in the brain and 31 pairs of spinal nerves that branch off of the spinal cord. The cranial nerves have various sensory and motor functions, and the spinal nerves branch into plexuses that innervate different body regions. The autonomic nervous system, a division of the PNS, regulates involuntary functions and has sympathetic and parasympathetic divisions that work in opposition to activate "fight or flight" responses or rest and digest functions.
The central nervous system consists of the brain and spinal cord, which are covered by three layers of meninges. The brain is divided into the forebrain, midbrain, and hindbrain. The forebrain includes the cerebrum and diencephalon. The cerebrum is made up of four lobes that control functions like movement, sensation, thought, and memory. The diencephalon contains the thalamus and hypothalamus, which relay sensory information and control autonomic functions respectively. The midbrain relays information between the brain and spinal cord. The hindbrain contains the cerebellum, pons, and medulla, which coordinate movement, relay information, and control vital functions. The spinal
Neurotransmitters are endogenous chemicals that enable communication between neurons. They are released from synaptic vesicles into the synaptic cleft and bind to receptors on the target neuron. There are various types of neurotransmitters classified by their chemical composition and function, including amino acids, gases, and peptides. Neurotransmitters have many functions, such as affecting movement, learning, mood, and metabolism.
A synapse is the junction between neurons that allows communication in one direction. There are chemical and electrical synapses classified by their structure and function. A chemical synapse contains synaptic vesicles that release neurotransmitters, which then bind to receptors on the target cell.
A reflex is an involuntary motor response to a stimulus without brain involvement. A reflex arc is
The nervous system is the body's control and communication system that regulates all bodily functions. It has two main parts - the central nervous system consisting of the brain and spinal cord, and the peripheral nervous system made up of nerves outside the brain and spinal cord. The nervous system contains neurons, or nerve cells, which receive and transmit electrochemical signals, as well as neuroglial cells that support and protect neurons. The neuron is the basic structural and functional unit of the nervous system.
This document discusses water, electrolyte, and pH balance in the human body. It contains the following key points:
- 60% of body weight is composed of body fluid, which is divided into intracellular and extracellular compartments. Electrolytes like sodium, potassium, and chloride are important components of body fluids.
- The body maintains water and electrolyte balance through mechanisms like osmoreception, thirst, ADH release, and kidney regulation of reabsorption and excretion.
- The body also maintains acid-base balance through buffer systems like bicarbonate, phosphate, and proteins. Chemical buffers, the lungs, and kidneys all work to regulate pH levels and compensate for acidosis or alk
How to Control Your Asthma Tips by gokuldas hospital.Gokuldas Hospital
Respiratory issues like asthma are the most sensitive issue that is affecting millions worldwide. It hampers the daily activities leaving the body tired and breathless.
The key to a good grip on asthma is proper knowledge and management strategies. Understanding the patient-specific symptoms and carving out an effective treatment likewise is the best way to keep asthma under control.
Cell Therapy Expansion and Challenges in Autoimmune DiseaseHealth Advances
There is increasing confidence that cell therapies will soon play a role in the treatment of autoimmune disorders, but the extent of this impact remains to be seen. Early readouts on autologous CAR-Ts in lupus are encouraging, but manufacturing and cost limitations are likely to restrict access to highly refractory patients. Allogeneic CAR-Ts have the potential to broaden access to earlier lines of treatment due to their inherent cost benefits, however they will need to demonstrate comparable or improved efficacy to established modalities.
In addition to infrastructure and capacity constraints, CAR-Ts face a very different risk-benefit dynamic in autoimmune compared to oncology, highlighting the need for tolerable therapies with low adverse event risk. CAR-NK and Treg-based therapies are also being developed in certain autoimmune disorders and may demonstrate favorable safety profiles. Several novel non-cell therapies such as bispecific antibodies, nanobodies, and RNAi drugs, may also offer future alternative competitive solutions with variable value propositions.
Widespread adoption of cell therapies will not only require strong efficacy and safety data, but also adapted pricing and access strategies. At oncology-based price points, CAR-Ts are unlikely to achieve broad market access in autoimmune disorders, with eligible patient populations that are potentially orders of magnitude greater than the number of currently addressable cancer patients. Developers have made strides towards reducing cell therapy COGS while improving manufacturing efficiency, but payors will inevitably restrict access until more sustainable pricing is achieved.
Despite these headwinds, industry leaders and investors remain confident that cell therapies are poised to address significant unmet need in patients suffering from autoimmune disorders. However, the extent of this impact on the treatment landscape remains to be seen, as the industry rapidly approaches an inflection point.
These lecture slides, by Dr Sidra Arshad, offer a simplified look into the mechanisms involved in the regulation of respiration:
Learning objectives:
1. Describe the organisation of respiratory center
2. Describe the nervous control of inspiration and respiratory rhythm
3. Describe the functions of the dorsal and respiratory groups of neurons
4. Describe the influences of the Pneumotaxic and Apneustic centers
5. Explain the role of Hering-Breur inflation reflex in regulation of inspiration
6. Explain the role of central chemoreceptors in regulation of respiration
7. Explain the role of peripheral chemoreceptors in regulation of respiration
8. Explain the regulation of respiration during exercise
9. Integrate the respiratory regulatory mechanisms
10. Describe the Cheyne-Stokes breathing
Study Resources:
1. Chapter 42, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 36, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 13, Human Physiology by Lauralee Sherwood, 9th edition
NAVIGATING THE HORIZONS OF TIME LAPSE EMBRYO MONITORING.pdfRahul Sen
Time-lapse embryo monitoring is an advanced imaging technique used in IVF to continuously observe embryo development. It captures high-resolution images at regular intervals, allowing embryologists to select the most viable embryos for transfer based on detailed growth patterns. This technology enhances embryo selection, potentially increasing pregnancy success rates.
Breast cancer: Post menopausal endocrine therapyDr. Sumit KUMAR
Breast cancer in postmenopausal women with hormone receptor-positive (HR+) status is a common and complex condition that necessitates a multifaceted approach to management. HR+ breast cancer means that the cancer cells grow in response to hormones such as estrogen and progesterone. This subtype is prevalent among postmenopausal women and typically exhibits a more indolent course compared to other forms of breast cancer, which allows for a variety of treatment options.
Diagnosis and Staging
The diagnosis of HR+ breast cancer begins with clinical evaluation, imaging, and biopsy. Imaging modalities such as mammography, ultrasound, and MRI help in assessing the extent of the disease. Histopathological examination and immunohistochemical staining of the biopsy sample confirm the diagnosis and hormone receptor status by identifying the presence of estrogen receptors (ER) and progesterone receptors (PR) on the tumor cells.
Staging involves determining the size of the tumor (T), the involvement of regional lymph nodes (N), and the presence of distant metastasis (M). The American Joint Committee on Cancer (AJCC) staging system is commonly used. Accurate staging is critical as it guides treatment decisions.
Treatment Options
Endocrine Therapy
Endocrine therapy is the cornerstone of treatment for HR+ breast cancer in postmenopausal women. The primary goal is to reduce the levels of estrogen or block its effects on cancer cells. Commonly used agents include:
Selective Estrogen Receptor Modulators (SERMs): Tamoxifen is a SERM that binds to estrogen receptors, blocking estrogen from stimulating breast cancer cells. It is effective but may have side effects such as increased risk of endometrial cancer and thromboembolic events.
Aromatase Inhibitors (AIs): These drugs, including anastrozole, letrozole, and exemestane, lower estrogen levels by inhibiting the aromatase enzyme, which converts androgens to estrogen in peripheral tissues. AIs are generally preferred in postmenopausal women due to their efficacy and safety profile compared to tamoxifen.
Selective Estrogen Receptor Downregulators (SERDs): Fulvestrant is a SERD that degrades estrogen receptors and is used in cases where resistance to other endocrine therapies develops.
Combination Therapies
Combining endocrine therapy with other treatments enhances efficacy. Examples include:
Endocrine Therapy with CDK4/6 Inhibitors: Palbociclib, ribociclib, and abemaciclib are CDK4/6 inhibitors that, when combined with endocrine therapy, significantly improve progression-free survival in advanced HR+ breast cancer.
Endocrine Therapy with mTOR Inhibitors: Everolimus, an mTOR inhibitor, can be added to endocrine therapy for patients who have developed resistance to aromatase inhibitors.
Chemotherapy
Chemotherapy is generally reserved for patients with high-risk features, such as large tumor size, high-grade histology, or extensive lymph node involvement. Regimens often include anthracyclines and taxanes.
Are you looking for a long-lasting solution to your missing tooth?
Dental implants are the most common type of method for replacing the missing tooth. Unlike dentures or bridges, implants are surgically placed in the jawbone. In layman’s terms, a dental implant is similar to the natural root of the tooth. It offers a stable foundation for the artificial tooth giving it the look, feel, and function similar to the natural tooth.
The skin is the largest organ and its health plays a vital role among the other sense organs. The skin concerns like acne breakout, psoriasis, or anything similar along the lines, finding a qualified and experienced dermatologist becomes paramount.
Osteoporosis - Definition , Evaluation and Management .pdfJim Jacob Roy
Osteoporosis is an increasing cause of morbidity among the elderly.
In this document , a brief outline of osteoporosis is given , including the risk factors of osteoporosis fractures , the indications for testing bone mineral density and the management of osteoporosis
Travel vaccination in Manchester offers comprehensive immunization services for individuals planning international trips. Expert healthcare providers administer vaccines tailored to your destination, ensuring you stay protected against various diseases. Conveniently located clinics and flexible appointment options make it easy to get the necessary shots before your journey. Stay healthy and travel with confidence by getting vaccinated in Manchester. Visit us: www.nxhealthcare.co.uk
Kosmoderma Academy, a leading institution in the field of dermatology and aesthetics, offers comprehensive courses in cosmetology and trichology. Our specialized courses on PRP (Hair), DR+Growth Factor, GFC, and Qr678 are designed to equip practitioners with advanced skills and knowledge to excel in hair restoration and growth treatments.
Travel Clinic Cardiff: Health Advice for International TravelersNX Healthcare
Travel Clinic Cardiff offers comprehensive travel health services, including vaccinations, travel advice, and preventive care for international travelers. Our expert team ensures you are well-prepared and protected for your journey, providing personalized consultations tailored to your destination. Conveniently located in Cardiff, we help you travel with confidence and peace of mind. Visit us: www.nxhealthcare.co.uk
Co-Chairs, Val J. Lowe, MD, and Cyrus A. Raji, MD, PhD, prepared useful Practice Aids pertaining to Alzheimer’s disease for this CME/AAPA activity titled “Alzheimer’s Disease Case Conference: Gearing Up for the Expanding Role of Neuroradiology in Diagnosis and Treatment.” For the full presentation, downloadable Practice Aids, and complete CME/AAPA information, and to apply for credit, please visit us at https://bit.ly/3PvVY25. CME/AAPA credit will be available until June 28, 2025.
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptxHolistified Wellness
We’re talking about Vedic Meditation, a form of meditation that has been around for at least 5,000 years. Back then, the people who lived in the Indus Valley, now known as India and Pakistan, practised meditation as a fundamental part of daily life. This knowledge that has given us yoga and Ayurveda, was known as Veda, hence the name Vedic. And though there are some written records, the practice has been passed down verbally from generation to generation.
Summer is a time for fun in the sun, but the heat and humidity can also wreak havoc on your skin. From itchy rashes to unwanted pigmentation, several skin conditions become more prevalent during these warmer months.
2. Cardiovascular System
The cardiovascular (cardio – heart, vascular – blood
vessels) system is divided for descriptive purposes into two
main parts:
The heart, whose pumping action ensures constant
circulation of the blood
The blood vessels, which form a lengthy network through
which the blood flows.
3. Organs Of Cardiovascular System
Blood: It is a fluid connective tissue.
Blood vessel: It is the channel in which blood is flowing.
Heart: It is a muscular blood pumping organ.
4. Blood Vessels
Blood vessels vary in structure,
size and function, and there are
several types:
Arteries
Arterioles
Capillaries
Venules
Veins
arterioles
venules
6. Arteries And Arterioles
These blood vessels transport blood away from the heart.
They vary considerably in size and their walls consist of three
layers of tissue:
tunica adventitia or outer layer of fibrous tissue
tunica media or middle layer of smooth muscle and elastic
tissue
tunica intima or inner lining of squamous epithelium called
endothelium.
7. Arteries And Arterioles
The amount of muscular and elastic tissue
varies in the arteries depending upon their size
and function.
In the large arteries, including the aorta,
sometimes called elastic arteries, the tunica
media contains more elastic tissue and less
smooth muscle.
This allows the vessel wall to stretch,
absorbing the pressure wave generated by the
heart as it beats.
8. Arteries And Arterioles
These proportions gradually change as the arteries branch many
times and become smaller until in the arterioles (the smallest
arteries) the tunica media consists almost entirely of smooth
muscle.
This enables their diameter to be precisely controlled, which
regulates the pressure within them.
Arteries have thicker walls than veins to withstand the high
pressure of arterial blood.
9. Anastomoses And End-arteries
Anastomoses are arteries that form a link between main
arteries supplying an area, e.g. the arterial supply to the palms of
the hand and soles of the feet, the brain, the joints and, to a
limited extent, the heart muscle.
If one artery supplying the area is occluded, anastomotic arteries
provide a collateral circulation.
This is most likely to provide an adequate blood supply when the
occlusion occurs gradually, giving the anastomotic arteries time
to dilate.
10. Anastomoses And End-arteries
An end-artery is an artery that is the sole source of blood to a
tissue, e.g. the branches from the circulus arteriosus (circle of
Willis) in the brain or the central artery to the retina of the eye.
When an end-artery is occluded the tissues it supplies die
because there is no alternative blood supply.
11. Capillaries And Sinusoids
The smallest arterioles break up into a number of minute vessels
called capillaries.
Capillary walls consist of a single layer of endothelial cells sitting
on a very thin basement membrane, through which water and
other small molecules can pass.
Blood cells and large molecules such as plasma proteins do not
normally pass through capillary walls.
The capillaries form a vast network of tiny vessels that link the
smallest arterioles to the smallest venules.
12. Capillaries And Sinusoids
In certain places, including the liver and bone marrow, the
capillaries are significantly wider and leakier than normal.
These capillaries are called sinusoids and because their walls
are incomplete and their lumen is much larger than usual, blood
flows through them more slowly under less pressure and can
come directly into contact with the cells outside the sinusoid wall.
This allows much faster exchange of substances between the
blood and the tissues.
13. Capillary Refill Time
When an area of skin is pressed firmly with a finger, it turns white
(blanches) because the blood in the capillaries under the finger
has been squeezed out.
Normally it should take less than two seconds for the capillaries to
refill once the finger is removed, and for the skin to turn pink
again.
Although the test may produce unreliable results, particularly in
adults, its use in children can be useful and a prolonged capillary
refill time suggests poor perfusion or dehydration.
14. Veins And Venules
Veins return blood at low pressure to the heart.
The walls of the veins are thinner than arteries but have the
same three layers of tissue .
They are thinner because there is less muscle and elastic
tissue in the tunica media, as veins carry blood at a lower
pressure than arteries.
When cut, the veins collapse while the thicker-walled
arteries remain open. When an artery is cut blood spurts at
high pressure while a slower, steady flow of blood escapes
15. Veins And Venules
Some veins possess valves, which prevent backflow of blood, ensuring that it
flows towards the heart.
They are formed by a fold of tunica intima and strengthened by connective
tissue.
The cusps are semilunar in shape with the concavity towards the heart.
Valves are abundant in the veins of the limbs.
They are absent in very small and very large veins in the thorax and abdomen.
Valves are assisted in maintaining one-way flow by skeletal muscles
surrounding the veins.
16. Veins And Venules
The smallest veins are called venules.
Veins are called capacitance vessels because they are
distensible, and therefore have the capacity to hold a large
proportion of the body’s blood.
17. Types Of Blood Vessels On The Basis Of Function
Conducting vessels
Distributing vessels
Resistance vessels
Exchanging vessels
Capacitance vessels
18. Blood Supply Of Blood Vessels
The outer layers of tissue of thick-walled blood vessels
receive their blood supply via a network of blood vessels
called the vasa vasorum.
Thin-walled vessels and the endothelium of the others
receive oxygen and nutrients by diffusion from the blood
passing through them.
19. Blood Vessel Diameter And Blood Flow
Resistance to flow of fluids along a tube is determined by three factors: the
diameter of the tube; the length of the tube; and the viscosity of the fluid.
The most important factor determining how easily the blood flows through
blood vessels is the diameter of the resistance vessels (the peripheral
resistance).
The length of the vessels and viscosity of blood also contribute to peripheral
resistance, but in health these are constant and are therefore not significant
determinants of changes in blood flow.
Peripheral resistance is a major factor in blood pressure regulation.
Constant adjustment of blood vessel diameter helps to regulate peripheral
20. Differences Between Artery And Vein
SN Arteries Vein
1 Arteries carry oxygenated blood,
away from heart except pulmonary
artery
Veins carry deoxygenated blood,
towards the heart except pulmonary
vein
2 These are mostly deeply situated in
the body.
These are superficial an deep in
location.
3 They have thick wall. They have thin wall.
4 They pass narrow lumen. They pass wide lumen.
5 They are reddish in color. They are bluish in color.
6 Arteries blood pressure is high. Veins blood pressure is low.
7 High elasticity. Low elasticity.
8 Internal valves are absent. Internal valves are present.
21. Thrombus and Embolus
A blood clot formed within the heart or blood vessels from the
constitute of blood, causing obstruction of blood vessel is known as
thrombus.
Embolus or embolism is a mass of undissolved matter present in the
blood vessel or lymphatic vessel causing obstruction, which is brought
there by blood or lymph and it may be solid, liquid or gaseous.
22. Heart
The heart is a roughly cone-
shaped hollow muscular organ.
It is about 10 cm long and is about
the size of the owner’s fist.
It weighs about 225 g in women
and is heavier in men (about 310
g).
23. Position of heart
The heart lies in the thoracic cavity in the
mediastinum (the space between the
lungs).
Vertebral level: 5th to 8th thoracic
vertebrae
It lies obliquely, a little more to the left
than the right, and presents a base
above, and an apex below.
The apex is about 9 cm to the left of the
midline at the level of the 5th intercostal
space, i.e. a little below the nipple and
slightly nearer the midline.
24. Apex Beat
The apex is the tip or summit of the heart and the apex beat is
the impact of the organ against the chest wall during systole.
The normal apex beat can be palpated in the pericardium on left
5th intercostal space.
In children apex beat occurs 4th intercostal space medial to
nipple.
Importance Of Apex Beat
Measurement of heart rate
Position of heart
Diagnosis of different heart diseases.
25. External Structure Of Heart
Surfaces of heart
Anterior surface
Inferior surface
Posterior surface
Right and left pulmonary surface
The coronary sulcus circles the heart, separating atria from the ventricle.
The anterior and posterior interventricular sulcus separates the two ventricles.
26. Organs associated with the
heart
Inferiorly – the apex rests on the central
tendon of the diaphragm
Superiorly – the great blood vessels, i.e.
the aorta, superior vena cava, pulmonary
artery and pulmonary veins
Posteriorly – the oesophagus, trachea,
left and right bronchus, descending aorta,
inferior vena cava and thoracic vertebrae
Laterally – the lungs – the left lung
overlaps the left side of the heart
Anteriorly – the sternum, ribs and
27. Structure Of Heart
The heart wall
The heart wall is composed of
three layers of tissue:
Pericardium
Myocardium and
Endocardium.
28. Pericardium
The pericardium is the outermost layer
and is made up of two sacs.
The outer sac (the fibrous pericardium)
consists of fibrous tissue and the inner
(the serous pericardium) of a
continuous double layer of serous
membrane.
The outer layer of the serous
pericardium, the parietal pericardium,
lines the fibrous pericardium. The inner
layer, the visceral pericardium, which is
continuous with the parietal pericardium,
is adherent to the heart muscle.
29. Pericardial Fluid
The serous membrane consists of flattened epithelial cells. It
secretes serous fluid, called pericardial fluid, into the space
between the visceral and parietal layers, which allows
smooth movement between them when the heart beats.
30. Myocardium
The myocardium is composed of
specialized cardiac muscle found only in
the heart.
It is striated, like skeletal muscle, but is
not under voluntary control.
Each fiber (cell) has a nucleus and one or
more branches.
The ends of the cells and their branches
are in very close contact with the ends
and branches of adjacent cells.
Microscopically these ‘joints’, or
intercalated discs, are thicker, darker lines
than the striations.
The myocardium is thickest at the apex
and thins out towards the base
31. Endocardium
This lines the chambers and valves of the heart.
It is a thin, smooth membrane to ensure smooth flow of
blood through the heart.
It consists of flattened epithelial cells, and it is continuous
with the endothelium lining the blood vessels.
32. Interior Of The Heart
Consists of
Chambers Of Heart(four)
Right Atrium
Right Ventricle
Left Atrium
Left Ventricle
Valves Of Heart
Atrioventricular Valve
Bicuspid Valve
Tricuspid Valve
Semi Lunar Valve
Pulmonary Valve
Aortic Valve
33. Chambers Of The Heart
Heart is made up of four chambers. Upper two chambers are known as
atrium and lower two chambers are known as ventricles.
Right Atrium
The right atrium serves as the receiving chamber for blood returning to the
heart from the systemic circulation.
The two major systemic veins, the superior and inferior venae cava, and the
large coronary vein called the coronary sinus that drains the heart
myocardium empty into the right atrium.
The superior vena cava drains blood from regions superior to the diaphragm:
the head, neck, upper limbs, and the thoracic region.
The inferior vena cava drains blood from areas inferior to the diaphragm: the
lower limbs and abdominopelvic region of the body.
The atria receive venous blood on a nearly continuous basis, preventing
venous flow from stopping while the ventricles are contracting. The opening
between the atrium and ventricle is guarded by the tricuspid valve.
34. Right Ventricle
The right ventricle receives blood from the right atrium through the
tricuspid valve.
Each flap of the valve is attached to strong strands of connective
tissue, the chordae tendineae, They connect each of the flaps to a
papillary muscle. There are three papillary muscles.
When the right ventricle contracts, it ejects blood into the pulmonary
trunk, which branches into the left and right pulmonary arteries that
carry it to each lung.
At the base of the pulmonary trunk is the pulmonary semilunar valve
that prevents backflow from the pulmonary trunk.
35. Left Atrium
After exchange of gases in the pulmonary capillaries, blood
returns to the left atrium high in oxygen via one of the four
pulmonary veins.
The opening between the left atrium and ventricle is
guarded by the mitral valve.
36. Left Ventricle
The muscular layer is much thicker in the left ventricle
compared to the right.
The mitral valve is connected to papillary muscles via chordae
tendineae.
There are two papillary muscles.
The left ventricle is the major pumping chamber for the
systemic circuit; it ejects blood into the aorta through the aortic
semilunar valve.
37. Valves Of Heart
Atrioventricular Valve:
Right atrioventricular valve: it lies between
right atrium and right ventricle. It is also
known as tricuspid valve. It has three flaps.
Left atrioventricular valve: it lies between left
atrium and left ventricle. It is also known as
bicuspid valve or mitral valve. It has two flaps.
Semilunar Valve: these are the two types of
valve found on the main branch of arteries
Pulmonary valve: it lies in the opening of
pulmonary trunk.
Aortic valve: it lies in the opening of aorta.
39. Interior Of The Heart
The heart is divided into a right and left side by the septum.
Each side is divided by an atrioventricular valve into the upper
atrium and the ventricle below.
The right atrioventricular valve (tricuspid valve) has three flaps
or cusps and the left atrioventricular valve (mitral valve) has two
cusps.
Flow of blood in the heart is one way; blood enters the heart via
the atria and passes into the ventricles below.
40. Interior Of The Heart
The valves between the atria and ventricles open and close
passively according to changes in pressure in the chambers.
They open when the pressure in the atria is greater than that in
the ventricles.
During ventricular systole (contraction) the pressure in the
ventricles rises above that in the atria and the valves snap shut,
preventing backward flow of blood prevented from opening
upwards into the atria by tendinous cords, called chordae
tendineae attached to papillary muscles.
41.
42. Flow Of Blood Through The Heart
The two largest veins of the body, the
superior and inferior venae cava, empty
their contents into the right atrium.
This blood passes via the right
atrioventricular valve into the right
ventricle, and from there is pumped into
the pulmonary artery or trunk (the only
artery in the body which carries
deoxygenated blood). The opening of the
pulmonary artery is guarded by the
pulmonary valve, formed by three
semilunar cusps. This valve prevents the
backflow of blood into the right ventricle
when the ventricular muscle relaxes.
43. Flow Of Blood Through The Heart
After leaving the heart the pulmonary artery
divides into left and right pulmonary
arteries, which carry the venous blood to the
lungs where exchange of gases takes place:
carbon dioxide is excreted and oxygen is
absorbed.
Two pulmonary veins from each lung carry
oxygenated blood back to the left atrium.
Blood then passes through the left
atrioventricular valve into the left ventricle,
and from there it is pumped into the aorta, the
first artery of the general circulation. The
opening of the aorta is guarded by the aortic
valve, formed by three semilunar cusps
44. Blood Supply To The Heart (The
Coronary Circulation)
Arterial Supply
The heart is supplied with arterial blood by the
right and left coronary arteries, which branch
from the aorta immediately distal to the aortic
Valve.
The coronary arteries receive about 5% of the
blood pumped from the heart, This large blood
supply, of which a large proportion goes to the
left ventricle, highlights the importance of the
heart to body function.
The coronary arteries traverse the heart,
eventually forming a vast network of capillaries.
45. Branches Of Right Coronary Artery
Anterior ventricular branch
Marginal branch
Posterior ventricular branch
Posterior interventricular artery
Atrial branch
Branches Of Left Coronary Artery
Anterior interventricular branch
Circumflex artery
Left marginal branch
Anterior ventricular and posterior ventricular branch
Atrial branches
46. Venous Drainage
Most of the venous blood is
collected into a number of cardiac
veins that join to form the
coronary sinus, which opens into
the right atrium.
The remainder passes directly into
the heart chambers through little
venous channels.
48. Nerve Supply Of Heart
Sympathetic supply
From cardiac plexus formed from cervical and upper thoracic portion of sympathetic
trunk.
It increases the conductivity and contractility of heart muscles.
Sympathetic nerves supply the SA and AV nodes and the myocardium of atria
and ventricles, and stimulation increases the rate and force of the heartbeat.
Parasympathetic supply
From vagus nerve
It decreases conductivity and contractility.
Supplies SA and AV nodes and atrial muscle. Vagal stimulation reduces the
rate at which impulses are produced, decreasing the rate and force of the
heartbeat.
49. Conducting System Of The Heart
The heart possesses the property of auto rhythmicity, which means it
generates its own electrical impulses and beats independently of
nervous or hormonal control, i.e. it is not reliant on external mechanisms
to initiate each heartbeat.
Small group of specialized neuromuscular cells in the myocardium
initiate and conduct impulses causing a co-ordinate and synchronized
contraction of heart muscles.
Components Of Conducting System
1. SA (Sinoatrial) node
2. AV(Atrioventricular) node
3. Bundle of His or AV Bundle
4. Subendocardial plexus of purkinje fibers
50. Sinoatrial node (SA node)
This small mass of specialized cells lies in the wall of the right atrium
near the opening of the superior vena cava.
The sinoatrial cells generate these regular impulses because they are
electrically unstable.
This instability leads them to discharge (depolarize) regularly, usually
between 60 and 80 times a minute.
This depolarization is followed by recovery (repolarization), but almost
immediately their instability leads them to discharge again, setting the
heart rate.
Because the SA node discharges faster than any other part of the heart,
it normally sets the heart rate and is called the pacemaker of the
heart.
Firing of the SA node triggers atrial contraction.
51. Atrioventricular node (AV node)
This small mass of neuromuscular tissue is situated in the wall of the
atrial septum near the atrioventricular valves.
Normally, the AV node merely transmits the electrical signals from
the atria into the ventricles.
There is a delay here; the electrical signal takes 0.1 of a second to
pass through into the ventricles. This allows the atria to finish
contracting before the ventricles start.
The AV node also has a secondary pacemaker function and takes
over this role if there is a problem with the SA node itself, or with the
transmission of impulses from the atria.
Its intrinsic firing rate, however, is slower than that set by the SA node
(40–60 beats per minute).
52. Atrioventricular bundle (AV bundle or bundle of His) and
Purkinje Fibers
This mass of specialized fibers originates from the AV node.
The AV bundle crosses the fibrous ring that separates atria and ventricles
then, at the upper end of the ventricular septum, it divides into right and
left bundle branches.
Within the ventricular myocardium the branches break up into fine fibers,
called the Purkinje fibers.
The AV bundle, bundle branches and Purkinje fibers transmit electrical
impulses from the AV node to the apex of the myocardium where the
wave of ventricular contraction begins, then sweeps upwards and
outwards, pumping blood into the pulmonary artery and the aorta.
53. Mechanism Of Action Of Conducting System
The impulses from SA node are conducted to
AV node by three types of internodal fibers.
All these fibers converge towards the AV
node and interdigitate with fibers of AV
node, the bundle of His arises and this
divides into right and left branches.
These branches run on either side of
interventricular septum and gives off
Purkinje fibers which spread all over the
ventricular myocardium.
54. The Cardiac Cycle
At rest, the healthy adult heart is likely to beat at a rate of 60–80
beats per minute (bpm). During each heartbeat, or cardiac
cycle, the heart contracts (systole) and then relaxes (diastole).
The rhythmic contraction and relaxation of heart chambers in
cyclic pattern is called cardiac cycle.
During each heart beat or cardiac cycle the heart contract and
then relax.
The period of contraction is called systole and relaxing period is
called diastole.
The complete cardiac cycle is of 0.8 seconds.
55. Stages Of The Cardiac Cycle
Taking 74 bpm as an example,
each cycle lasts about 0.8 of a
second and consists of:
Atrial Systole –
contraction of the atria
Ventricular Systole –
contraction of the ventricles
Complete Cardiac
Diastole – relaxation of the atria
and ventricles.
56. Arterial Systole
Simultaneous contraction of both atria.
Opens AV valves( bicuspid and tricuspid valves).
Blood flows within the ventricles of respective sides.
No heart sound is produced.
Completes within 0.1 sec.
57. Ventricular Systole
Simultaneous contraction of both ventricles.
Bicuspid and Tricuspid valves get closed so that first heart sound
(LUBB) is produced
Blood is forced into pulmonary artery and aorta.
It completes within 0.3 seconds.
58. Complete Cardiac Diastole
Relaxation of both atria and ventricles together.
Both atria gets filled with blood.
Pulmonary and aortic valves get closed to prevent backflow of
blood so that second heart sound(DUBB) is produced.
It completes within 0.4 seconds.
60. Control Of Cardiac Cycle
Intrinsic Control
The heart beat originates and is controlled by SA node present
within the heart. SA node rhythmically generates the impulses
throughout the life.
Extrinsic Control
Though cardiac impulse is self generated and controlled, it can be
changed extrinsically(outside the heart) by hormones and neural
impulses.
61. Extrinsic Control
Hormonal Control
Various hormones like thyroxin, insulin, adrenaline, nor adrenaline and
sex hormones directly act on the SA node stimulating and inhibiting the
cardiac impulse.
Neural Impulse
The cardiovascular area is situated in the medulla. Heart is under control
of autonomic nervous system. ANS have two group of nerve fibers:
sympathetic and parasympathetic. Vagus nerve from parasympathetic
nervous system slows the heart rate while sympathetic nerves accelerate
the heart beat.
62. Heart Sound
There are four heart sounds, each corresponding to a particular event in
the cardiac cycle. The first two are most easily distinguished, and sound
through the stethoscope like ‘lub dup’.
The first sound (S1), ‘lub’, is fairly loud and is due to the closure of the
atrioventricular valves. This corresponds with the start of ventricular
systole.
The second sound(S2), ‘dup’, is softer and is due to the closure of the
aortic and pulmonary valves. This corresponds with ventricular diastole.
In both cases, as the valves close, the openings within the atrioventricular
septum guarded by the valves will become reduced, and blood flow
through the opening will become more turbulent until the valves are fully
63. Heart Sound
There is a third heart sound, S3, but it is rarely heard in healthy
individuals. It may be the sound of blood flowing into the atria, or
blood sloshing back and forth in the ventricle, or even tensing of
the chordae tendineae. S3 may be heard in youth, some athletes,
and pregnant women. If the sound is heard later in life, it may
indicate congestive heart failure, warranting further tests.
The fourth heart sound, S4, results from the contraction of the
atria pushing blood into a stiff or hypertrophic ventricle, indicating
failure of the left ventricle. S4 occurs prior to S1
64. Heart Murmur
The term murmur is used to describe an unusual sound coming from the
heart that is caused by the turbulent flow of blood.
Murmurs are graded on a scale of 1 to 6, with 1 being the most common,
the most difficult sound to detect, and the least serious. The most severe is
a 6.
Phonocardiograms or auscultograms can be used to record both
normal and abnormal sounds using specialized electronic stethoscopes.
During auscultation, it is common practice for the clinician to ask the
patient to breathe deeply. This procedure not only allows for listening to
airflow, but it may also amplify heart murmurs. Inhalation increases blood
flow into the right side of the heart and may increase the amplitude of
right-sided heart murmurs. Expiration partially restricts blood flow into
the left side of the heart and may amplify left-sided heart murmurs.
67. Electrocardiogram (ECG)
The body tissues and fluids conduct electricity well, so
the electrical activity in the heart can be recorded on the
skin surface using electrodes positioned on the limbs
and/or the chest.
This recording, called an electrocardiogram (ECG)
shows the spread of the electrical signal generated by
the SA node as it travels through the atria, the AV node
and the ventricles.
The normal ECG tracing shows five waves which, by
convention, have been named P, Q, R, S and T.
The P wave arises when the impulse from the SA node
sweeps over the atria (atrial depolarization).
The QRS complex represents the very rapid spread of
the impulse from the AV node through the AV bundle and
the Purkinje fibers and the electrical activity of the
ventricular muscle (ventricular depolarization).
68. Electrocardiogram (ECG)
The T wave represents the relaxation of the ventricular
muscle (ventricular repolarisation).
Atrial repolarisation occurs during ventricular
contraction, and so is not seen because of the larger
QRS complex.
The ECG described above originates from the SA node
and is called sinus rhythm. The rate of sinus rhythm is
60–100 b.p.m. A faster heart rate is called tachycardia
and a slower heart rate, bradycardia.
By examining the pattern of waves and the time interval
between cycles and parts of cycles, information about
the state of the myocardium and the cardiac conduction
69. Electrocardiogram (ECG)
Careful analysis of the ECG reveals a detailed picture of
both normal and abnormal heart function, and is an
indispensable clinical diagnostic tool.
The standard electrocardiograph (the instrument that
generates an ECG) uses 3, 5, or 12 leads.
The greater the number of leads an electrocardiograph
uses, the more information the ECG provides.
The term “lead” may be used to refer to the cable from
the electrode to the electrical recorder, but it typically
describes the voltage difference between two of the
electrodes.
70. Electrocardiogram (ECG)
The 12-lead electrocardiograph uses 10
electrodes placed in standard locations on
the patient’s skin.
In continuous ambulatory
electrocardiographs, the patient wears a
small, portable, battery-operated device
known as a Holter monitor, or simply a
Holter, that continuously monitors heart
electrical activity, typically for a period of 24
hours during the patient’s normal routine.
73. Uses of ECG
Determining and diagnosis of
Hear rate
Heart rhythm
Abnormal electrical condition
Poor blood flow to heart muscle
Heart attack
Coronary heart disease
Hypertrophy of heart
74. Blood Pressure
Blood pressure is the force or pressure that the blood exerts on the walls
of blood vessels.
Systemic arterial blood pressure maintains the essential flow of blood into
and out of the organs of the body.
Keeping blood pressure within normal limits is very important.
If it becomes too high, blood vessels can be damaged, causing clots or
bleeding from sites of blood vessel rupture.
If it falls too low, then blood flow through tissue beds may be inadequate.
This is particularly dangerous for essential organs such as the heart, brain
or kidneys.
75. Blood Pressure
The systemic arterial blood pressure, usually called simply arterial
blood pressure, is the result of the discharge of blood from the left
ventricle into the already full aorta.
Blood pressure varies according to the time of day, the posture,
gender and age of the individual.
Blood pressure falls at rest and during sleep.
It increases with age and is usually higher in women than in men.
76. Systolic And Diastolic Pressures
When the left ventricle contracts and pushes blood into the aorta, the
pressure produced within the arterial system is called the systolic blood
pressure. In adults it is about 120 mmHg.
In complete cardiac diastole when the heart is resting following the ejection of
blood, the pressure within the arteries is much lower and is called diastolic
blood pressure. In an adult this is about 80 mmHg.
The difference between systolic and diastolic blood pressures is the pulse
pressure.
Arterial blood pressure (BP) is measured with a sphygmomanometer and is
usually expressed with the systolic pressure written above the diastolic
pressure.
77. Types Of Blood Pressure
Systolic Blood Pressure
This is the maximum pressure exerted in the arteries during the systole of
heart. The normal systolic pressure is 120mm of Hg.
Diastolic Blood Pressure
This is the minimum pressure in the arteries during the diastole of heart.
The normal diastolic blood pressure is 80 mm of Hg.
Pulse Pressure
This is the differences between the systolic and diastolic pressure.
Normally it is 40 mm of Hg.
78. Factors Determining Blood Pressure
Blood pressure is determined by cardiac output and
peripheral resistance. Change in either of these parameters
tends to alter systemic blood pressure, although the body’s
compensatory mechanisms usually adjust for any significant
change.
Blood pressure = Cardiac output X Peripheral resistance
79. Factors Affecting Blood Pressure
Cardiac output
Peripheral resistance
Age
Sex
Posture is recumbent position
Exercise
Emotion and Excitement
Temperature
Blood volume
80. Cardiac Output
The cardiac output is the amount of blood ejected from each
ventricle every minute. The amount expelled by each contraction
of each ventricle is the stroke volume.
Cardiac output = Stroke volume X Heart rate.
In a healthy adult at rest, the stroke volume is approximately 70
mL and if the heart rate is 72 per minute, the cardiac output is 5
L/minute.
This can be greatly increased to meet the demands of exercise to
around 25 L/minute, and in athletes up to 35 L/minute. This
increase during exercise is called the cardiac reserve.
81. Stroke Volume
The stroke volume is determined by the volume of blood in
the ventricles immediately before they contract, i.e. the
ventricular end-diastolic volume (VEDV), sometimes
called preload. In turn, preload depends on the amount of
blood returning to the heart through the superior and
inferior venae cava (the venous return).
82. Factors Affecting Stroke Volume
VEDV (ventricular end-diastolic volume – preload)
Venous return
position of the body
skeletal muscle pump
respiratory pump
Strength of myocardial contraction
Blood volume
83. Heart Rate
Heart rate is the speed of the heart beat measured by the number of
contractions (beats) of the heart per minute (bpm).
The Main Factors Affecting Heart Rate
Gender
Autonomic activity
Age
Circulating hormones
Activity and exercise
Temperature
The baroreceptor reflex
Emotional states
84. Control Of Blood Pressure (BP)
Blood pressure is controlled in two ways:
short-term control, on a moment-to-moment basis, which mainly
involves the baroreceptor reflex, discussed below, and also
chemoreceptors and circulating hormones
long-term control, which involves regulation of blood volume by
the kidneys and the renin–angiotensin aldosterone system.
85. Short-term Blood Pressure Regulation
The cardiovascular center (CVC) is a collection of interconnected
neurons in the medulla and pons of the brain stem. The CVC
receives, integrates and coordinates inputs from:
baroreceptors (pressure receptors)
Chemoreceptors
higher centers in the brain.
The CVC sends autonomic nerves (both sympathetic and
parasympathetic) to the heart and blood vessels. It controls BP by
slowing down or speeding up the heart rate and by dilating or
constricting blood vessels. Activity in these fibers is essential for
control of blood pressure.
86. Long-term Blood Pressure Regulation
Slower, longer lasting changes in blood pressure are effected by
the renin–angiotensin–aldosterone system (RAAS) and the action
of antidiuretic hormone (ADH).
Both of these systems regulate blood volume, thus influencing
blood pressure.
In addition, atrial natriuretic peptide (ANP), a hormone released by
the heart itself, causes sodium and water loss from the kidney and
reduces blood pressure, opposing the activities of both ADH and
the RAAS.
87. Pulse
The pulse can be felt with gentle finger pressure in a superficial artery
when its wall is distended by blood pumped from the left ventricle during
contraction (systole).
The wave passes quickly as the arterial wall recoils.
Each contraction of the left ventricle forces about 60–80 mm of blood
through the already full aorta and into the arterial system.
The aortic pressure wave is transmitted through the arterial system and
can be felt at any point where a superficial artery can be pressed firmly
but gently against a bone.
88. Pulse
The number of pulse b.p.m. normally represents the heart rate and
varies considerably in different people and in the same person at
different times.
An average of 60–80 is common at rest. Information that may be
obtained from the pulse includes:
the rate at which the heart is beating
the regularity of the heartbeat
the artery wall should feel soft and pliant under the fingers.
89. Pulse Rate
In health, the pulse rate and the heart rate are identical.
In certain circumstances, the pulse may be less than the heart rate.
This may occur, for example, if:
The arteries supplying the peripheral tissues are narrowed or
blocked and the blood therefore is not pumped through them with each
heartbeat. Provided enough blood is reaching an extremity to nourish it, it
will remain pink in colour and warm to touch, even if the pulse cannot be
felt
There is some disorder of cardiac contraction, e.g. atrial fibrillation and
the heart is unable to generate enough force, with each contraction, to
circulate blood to the peripheral arteries.
90. Factors Affecting The Pulse Rate
Age
Gender
Body built
Exercise activity
Stress and emotions
Body temperature
Blood volume
91. Normal Pulse Rate According To Age
Infants 100-160
Preschoolers 80-110
School age 70-100
Adolescent 60-90
Adult 60-100
94. Circulation Of Blood
The movement and distribution of blood in body in different organs
through blood vessels is called circulation.
Circulation in our body are mainly of four types:
Pulmonary Circulation
Systemic Or General Circulation
Portal Circulation
Coronary Circulation
95. Pulmonary Circulation
This is the circulation of blood from the right ventricle of the heart to the lungs and back
to the left atrium. In the lungs, carbon dioxide is excreted and oxygen is absorbed.
The pulmonary artery or trunk, carrying deoxygenated blood, leaves the upper part of
the right ventricle of the heart.
It passes upwards and divides into left and right pulmonary arteries which enters to
the left and right lungs respectively.
Within the lung these arteries divide and subdivide into smaller arteries, arterioles and
capillaries.
96. Pulmonary Circulation
The exchange of gases takes place between capillary blood and air in
the alveoli of the lungs.
In each lung the capillaries containing oxygenated blood merge into
progressively larger venules, and eventually form two pulmonary veins.
Two pulmonary veins leave each lung, returning oxygenated blood to the
left atrium of the heart.
In this way the deoxygenated blood is pumped from right ventricle and the
oxygenated blood comes to the left atrium of heart is called pulmonary
circulation.
98. Systemic Circulation
The systemic circulation involves all the blood vessels of the body that are
not part of the pulmonary circulation. The oxygenated blood is pumped
out from the heart through aorta and received through vena cava in right
atrium is called systemic circulation.
The blood pumped out from the left ventricle is carried by the
branches of the aorta around the body and returns to the right
atrium of the heart by the superior and inferior vena cava.
99. Systemic Circulation
The blood from left ventricle is pumped out through aorta. The
branches of arch of aorta supply to head, neck and upper limb. The
thoracic aorta supplies blood to lungs, esophagus and muscles of
thoracic region. The abdominal aorta supplies stomach, spleen, liver,
intestines, reproductive organs and lower limb.
The blood is drained by superior and inferior vena cava. The blood
from upper limb, head and neck is drained by superior vena cava to
right atrium. The venous blood from lower limb, abdominal and pelvic
organs is drained by inferior vena cava into right atrium. The venous
blood from thoracic area is drained by azygous and hemiazygous
vein to superior vena cava.
101. Portal Circulation
In portal circulation, venous blood passes from the capillaries bed of
abdominal part of digestive system, spleen and pancreas to the liver.
It passes through a second capillary bed, the hepatic sinusoids in the
liver before entering the general circulation via the inferior vena cava.
In this way blood with high concentration of nutrients, absorbed from
the stomach and intestine goes to the liver.
103. Coronary Circulation
The heart is supplied with blood by the right and left coronary arteries.
Right coronary artery gives marginal, posterior interventricular
branches. Left coronary artery is larger branch and gives anterior
interventricular, circumflex and diagonal branches.
Most of the blood is collected by several small veins ( great cardiac,
middle cardiac, small cardiac, anterior cardiac, marginal) that joins to
form the coronary sinus which opens into the right atrium.
105. Importance Of Circulation
To carry O2, nutrition, vitamins to the tissue.
To carry away different metabolic waste products and CO2 from tissues
for elimination.
To prevent intravascular coagulation of blood.
Helps to maintain thermal balance throughout the body.