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The document describes the anatomy and function of the heart. It is divided into detailed sections on the right and left sides of the heart. The right side receives deoxygenated blood and pumps it to the lungs, while the left side receives oxygenated blood from the lungs and pumps it out to the body. Key components discussed include the atria, ventricles, valves, arteries and veins that allow blood to circulate through the heart and into the lungs or body as needed.
FMGE Handwritten Notes SAMPLE by MBBS HelpMBBS Help
MBBS Help offering Handwritten Note PDF by MIST Institute, 19 Subjects PDF available Anatomy, Anesthesia, Biochemistry, ENT, FMT, Gynecology, Medicine, Microbiology, Obstetrics, Ophthalmology Orthopedics, Pediatrics, Pathology, Pharmacology, Physiology, PSM, Psychiatry, Radiology and Surgery.
These Notes are digital colored PDF notes
VS- TEMPERATURE (NORMAL,FORMULA, TYPES OF THERMOMETER, THERMORECEPTORSDepEd
Vital signs such as body temperature, pulse rate, respiration rate, and blood pressure can detect medical problems and are commonly measured in medical settings and at home. The normal human body temperature can range from 97.8-99°F (36.5-37.2°C) and can be taken orally, rectally, in the armpit, ear, or on the forehead. The body tightly regulates its core temperature through thermoreceptors in the skin, the hypothalamus in the brain, and effectors like shivering muscles and sweating glands. Fevers, hyperthermia, and hypothermia occur when this system is disrupted and the body temperature rises or falls outside the normal
Visible Body - Sternocleidomastoid and the Scalene MusclesVisible Body
Learn about the anatomy and actions of the muscles in the neck region. Want more anatomy content? Check out the free Musculoskeletal Library! http://go.visiblebody.com/muscle-ebook-library-0
Arterial Pulse: Radial
To assess cardiac function. To assess state of health.
NEW BLOGSITE ADDRESS:
"Nurses Information Site"
http://nursesinfosite.blogspot.com
The heart is pyramidal in shape with an apex pointing leftward and downward. It has four chambers - two atria which receive blood and two ventricles which pump blood. The right atrium receives deoxygenated blood from the body and pumps it to the right ventricle to be sent to the lungs. The left atrium receives oxygenated blood from the lungs and pumps it to the left ventricle to be sent to the body. Blood flows through the heart via the tricuspid, bicuspid/mitral, pulmonary and aortic valves. The heart's conduction system coordinates contractions and is composed of the sinoatrial node, atrioventricular node and bundle of His.
The document summarizes the anatomy of the heart in three parts. It begins by describing the location, size, and external features of the heart. It then explains the internal structures of the heart including the layers of the heart wall, the four chambers, and the valves. It concludes by detailing the circulation of blood through the heart and lungs via the major vessels and coronary arteries.
The document discusses first aid, including its definition, principles, and history. It provides guidance on assessing safety, gaining access to victims, determining life threats, summoning help, and qualities of a first aider. Key first aid skills like controlling bleeding, treating shock, handling fractures, spinal and head injuries are summarized. Proper first aid kit contents and effective communication techniques are also outlined.
CPR involves chest compressions and rescue breathing to manually circulate blood to vital organs until a victim's heart can be restarted. It should be performed if someone is unresponsive and not breathing normally. The first step is calling emergency services before beginning CPR. CPR maintains oxygenated blood flow through chest compressions and rescue breaths based on the ABCs - Airway, Breathing, and Circulation. Even imperfect CPR is better than no aid, so bystanders should attempt it and continue until emergency help arrives.
FMGE Handwritten Notes SAMPLE by MBBS HelpMBBS Help
MBBS Help offering Handwritten Note PDF by MIST Institute, 19 Subjects PDF available Anatomy, Anesthesia, Biochemistry, ENT, FMT, Gynecology, Medicine, Microbiology, Obstetrics, Ophthalmology Orthopedics, Pediatrics, Pathology, Pharmacology, Physiology, PSM, Psychiatry, Radiology and Surgery.
These Notes are digital colored PDF notes
VS- TEMPERATURE (NORMAL,FORMULA, TYPES OF THERMOMETER, THERMORECEPTORSDepEd
Vital signs such as body temperature, pulse rate, respiration rate, and blood pressure can detect medical problems and are commonly measured in medical settings and at home. The normal human body temperature can range from 97.8-99°F (36.5-37.2°C) and can be taken orally, rectally, in the armpit, ear, or on the forehead. The body tightly regulates its core temperature through thermoreceptors in the skin, the hypothalamus in the brain, and effectors like shivering muscles and sweating glands. Fevers, hyperthermia, and hypothermia occur when this system is disrupted and the body temperature rises or falls outside the normal
Visible Body - Sternocleidomastoid and the Scalene MusclesVisible Body
Learn about the anatomy and actions of the muscles in the neck region. Want more anatomy content? Check out the free Musculoskeletal Library! http://go.visiblebody.com/muscle-ebook-library-0
Arterial Pulse: Radial
To assess cardiac function. To assess state of health.
NEW BLOGSITE ADDRESS:
"Nurses Information Site"
http://nursesinfosite.blogspot.com
The heart is pyramidal in shape with an apex pointing leftward and downward. It has four chambers - two atria which receive blood and two ventricles which pump blood. The right atrium receives deoxygenated blood from the body and pumps it to the right ventricle to be sent to the lungs. The left atrium receives oxygenated blood from the lungs and pumps it to the left ventricle to be sent to the body. Blood flows through the heart via the tricuspid, bicuspid/mitral, pulmonary and aortic valves. The heart's conduction system coordinates contractions and is composed of the sinoatrial node, atrioventricular node and bundle of His.
The document summarizes the anatomy of the heart in three parts. It begins by describing the location, size, and external features of the heart. It then explains the internal structures of the heart including the layers of the heart wall, the four chambers, and the valves. It concludes by detailing the circulation of blood through the heart and lungs via the major vessels and coronary arteries.
The document discusses first aid, including its definition, principles, and history. It provides guidance on assessing safety, gaining access to victims, determining life threats, summoning help, and qualities of a first aider. Key first aid skills like controlling bleeding, treating shock, handling fractures, spinal and head injuries are summarized. Proper first aid kit contents and effective communication techniques are also outlined.
CPR involves chest compressions and rescue breathing to manually circulate blood to vital organs until a victim's heart can be restarted. It should be performed if someone is unresponsive and not breathing normally. The first step is calling emergency services before beginning CPR. CPR maintains oxygenated blood flow through chest compressions and rescue breaths based on the ABCs - Airway, Breathing, and Circulation. Even imperfect CPR is better than no aid, so bystanders should attempt it and continue until emergency help arrives.
The document summarizes the anatomy of the head and mandible bone. It describes the different parts of the skull that make up the head, including the cranium, facial bones, and three ossicles in the middle ear. It then provides a detailed overview of the mandible bone, describing its body and ramus, as well as processes like the coronoid process, condylar process, and angle. It also outlines the bones that make up the maxilla.
The document discusses the diencephalon, which is a region of the brain situated between the cerebrum and brainstem. It consists of four main parts: the thalamus, hypothalamus, epithalamus, and subthalamus. The thalamus acts as a gateway to the cerebral cortex by integrating sensory information and influencing mood and emotions. The hypothalamus regulates vital functions such as body temperature, hunger, and circadian rhythms. Examville.com is an online learning site that offers practice tests, classes, tutoring, study guides, and premium content to help students prepare for exams.
Examville.com is a website that provides online practice tests, live classes, tutoring, study guides, Q&A, and premium content to help students prepare for exams. Collagen is the most abundant protein in mammals, making up about 25% of total protein content. It forms the main structure of connective tissue. Collagen has diverse structures tailored to its different functions, such as forming highly organized structures in tendons or loosely woven flexible fibers in skin. Tropocollagen molecules are composed of three polypeptide chains that form a stable triple helix structure through hydrogen bonding between chains. This triple helix structure gives collagen its great tensile strength.
The lymphatic system helps maintain fluid balance, absorb fat and fight infection. It is composed of lymph, lymph vessels, lymph nodes and organs like the spleen and thymus. Lymph vessels carry lymph fluid and drain into the subclavian veins. Lymph nodes filter the lymph and activate the immune system. The spleen, tonsils and thymus also help filter pathogens and mature lymphocytes to fight infection. The lymphatic system provides both nonspecific resistance through barriers and chemicals, as well as specific adaptive immunity mediated by B and T lymphocytes and antibodies.
The document discusses the adrenal glands and their hormones. It describes that the adrenal glands sit above the kidneys and contain an adrenal cortex and medulla. The cortex secretes corticosteroids like mineralocorticoids and glucocorticoids. Aldosterone is the main mineralocorticoid produced in the zona glomerulosa, while cortisol is the primary glucocorticoid from the zona fasciculata. Cortisol regulates blood glucose and sodium/potassium balance. The document also outlines the functions of aldosterone in increasing sodium reabsorption and potassium secretion in the kidneys.
Examville.com is a website that provides online practice tests, live classes, tutoring, study guides, Q&A, and premium content to help people prepare for exams. The document then discusses the key parts and features of the axial skeleton, including the vertebral column, ribs, sternum, and thorax. It also lists the bones and structures that make up the vertebral column, ribs, and sternum. The summary concludes by mentioning that joining Examville.com is free.
The document provides information about the muscular, circulatory, and lymphatic systems of the human body. It describes the key functions and components of each system. The muscular system section explains the different muscle types and how muscles are named and organized in the body. The circulatory system section outlines the heart structure and function and describes the arterial, venous, and capillary systems. The lymphatic system transports lymph and provides defense functions.
The document summarizes the structure and function of the integumentary system. It describes the two main layers of the skin - the epidermis and dermis - as well as additional structures like hair, nails, and glands. The skin provides protection, regulates temperature and fluid balance, and plays a role in sensation, blood storage, and metabolism. Key cell types in the epidermis include keratinocytes, melanocytes, Langerhans cells, and Merkel cells.
The document provides information about the structure and function of the human heart. It is divided into sections on the right heart and left heart. The right heart receives deoxygenated blood from the body and pumps it to the lungs. The left heart receives oxygenated blood from the lungs and pumps it out to the body through the aorta to support the systemic circulation. Key components include the right and left atria and ventricles, tricuspid and mitral valves, and major blood vessels like the vena cavae, pulmonary artery and veins, and aorta.
The document provides information about the structure and function of the human heart. It is divided into sections on the right heart and left heart. The right heart receives deoxygenated blood from the body and pumps it to the lungs. The left heart receives oxygenated blood from the lungs and pumps it out to the body through the aorta to support the systemic circulation. Key components include the right and left atria and ventricles, tricuspid and mitral valves, and major blood vessels like the vena cavae, pulmonary artery and veins, and aorta.
The document provides information about the structure and function of the human heart. It is divided into sections on the right heart and left heart. The right heart receives deoxygenated blood from the body and pumps it to the lungs. The left heart receives oxygenated blood from the lungs and pumps it out to the body through the aorta to sustain the circulatory system. Key components include the right and left atria and ventricles, tricuspid and mitral valves, and major blood vessels like the vena cavae, pulmonary artery and veins, and aorta.
The human heart is a muscular organ that pumps blood through the body. It is divided into four chambers - two atria that receive blood and two ventricles that pump blood out. The right side receives deoxygenated blood from the body and pumps it to the lungs. The left side receives oxygenated blood from the lungs and pumps it out to the body through the aorta. Valves control the direction of blood flow between the chambers and vessels. The heart is a vital organ that circulates blood continuously through two circuits - pulmonary circulation to the lungs and systemic circulation to the body.
The document describes the anatomy and structures of the heart. It discusses:
- The heart is surrounded by the pericardium, a double-walled sac that has an outer fibrous layer and inner serous layers separated by fluid.
- The heart has four chambers - two upper atria that receive blood and two lower ventricles that pump blood out. Blood flows through valves between the chambers.
- The heart wall has three layers - the outer epicardium, middle muscular myocardium, and inner endothelial endocardium.
- The heart is supplied by the right and left coronary arteries and drains into the coronary sinus vein.
- Nerves from the autonomic nervous system
The heart is a hollow, muscular organ located slightly left of center in the chest. It is surrounded by three layers of tissue - the outer fibrous pericardium, middle muscular myocardium, and inner endothelial endocardium. The heart is divided into four chambers - right atrium, right ventricle, left atrium, and left ventricle - with valves that ensure one-way blood flow. Deoxygenated blood enters the right atrium from the body and is pumped to the lungs via the right ventricle. Oxygenated blood returns to the left atrium from the lungs and is pumped back out to the body by the left ventricle.
The document summarizes the anatomy of the pericardium and heart. It describes the pericardium as a fibroserous sac that encloses the heart. It then discusses the layers of the pericardium - the fibrous pericardium and serous pericardium with its parietal and visceral layers. It also describes the surfaces, chambers, valves and conducting system of the heart.
The document describes the structure and function of the heart and circulatory system. It discusses the major veins that return deoxygenated blood to the right atrium, such as the superior and inferior vena cava. It also describes the four chambers of the heart, including the right and left atria that receive blood and the right and left ventricles that pump blood to the lungs and body. The valves such as the tricuspid and bicuspid valves prevent backflow of blood through the heart.
The document provides an overview of the human circulatory system, including:
- The heart pumps blood through vessels in a double circulatory system, with the pulmonary and systemic circuits.
- The heart has four chambers, with the right atrium and ventricle pumping to the lungs and the left pumping to the body. It is located in the mediastinum.
- Blood flows through one-way valves between the atria and ventricles, and into the pulmonary trunk and aorta.
- The cardiac conduction system coordinates heart chamber contractions for efficient blood flow.
The pericardium is a fibroserous sac that encloses and protects the heart. It has two layers - a fibrous outer layer and a serous inner layer. The heart has four chambers - right and left atria which receive blood, and right and left ventricles which pump blood out. Each chamber has a specific structure and function in the circulation. The heart also has a conducting system that generates electrical signals to coordinate contractions and pumping of the heart.
This presentation will help you to get to known about the human heart in very much clear way. It will help you alot in making your concepts clear regarding the human heart and it's functioning.
The document summarizes the anatomy of the cardio-vascular system of goats. It describes the heart which has four chambers - right atrium, right ventricle, left atrium and left ventricle. Blood enters the right atrium from the vena cava and is pumped to the right ventricle before entering the lungs via the pulmonary artery. Oxygenated blood returns from the lungs to the left atrium and is pumped to the left ventricle and then to the rest of the body via the aorta. It also outlines the major blood vessels including the aorta, anterior vena cava and posterior vena cava.
The heart is a hollow muscular organ responsible for pumping blood through the circulatory system. It has four chambers: right atrium, right ventricle, left atrium, and left ventricle. The heart is surrounded by membranes and has three layers - epicardium, myocardium, and endocardium. It is located in the chest cavity and pumps oxygenated blood received from the lungs through the left side of the heart to the entire body. The heart has four valves that prevent backflow of blood - tricuspid valve, pulmonary valve, mitral valve, and aortic valve.
The primitive blueprint for the heart and circulatory system emerged with the arrival of the third mesodermal germ layer in bilaterians. Since then, hearts in animals have evolved from a single layered tube to a multiple chambered heart in due course of time.
The document summarizes the anatomy of the head and mandible bone. It describes the different parts of the skull that make up the head, including the cranium, facial bones, and three ossicles in the middle ear. It then provides a detailed overview of the mandible bone, describing its body and ramus, as well as processes like the coronoid process, condylar process, and angle. It also outlines the bones that make up the maxilla.
The document discusses the diencephalon, which is a region of the brain situated between the cerebrum and brainstem. It consists of four main parts: the thalamus, hypothalamus, epithalamus, and subthalamus. The thalamus acts as a gateway to the cerebral cortex by integrating sensory information and influencing mood and emotions. The hypothalamus regulates vital functions such as body temperature, hunger, and circadian rhythms. Examville.com is an online learning site that offers practice tests, classes, tutoring, study guides, and premium content to help students prepare for exams.
Examville.com is a website that provides online practice tests, live classes, tutoring, study guides, Q&A, and premium content to help students prepare for exams. Collagen is the most abundant protein in mammals, making up about 25% of total protein content. It forms the main structure of connective tissue. Collagen has diverse structures tailored to its different functions, such as forming highly organized structures in tendons or loosely woven flexible fibers in skin. Tropocollagen molecules are composed of three polypeptide chains that form a stable triple helix structure through hydrogen bonding between chains. This triple helix structure gives collagen its great tensile strength.
The lymphatic system helps maintain fluid balance, absorb fat and fight infection. It is composed of lymph, lymph vessels, lymph nodes and organs like the spleen and thymus. Lymph vessels carry lymph fluid and drain into the subclavian veins. Lymph nodes filter the lymph and activate the immune system. The spleen, tonsils and thymus also help filter pathogens and mature lymphocytes to fight infection. The lymphatic system provides both nonspecific resistance through barriers and chemicals, as well as specific adaptive immunity mediated by B and T lymphocytes and antibodies.
The document discusses the adrenal glands and their hormones. It describes that the adrenal glands sit above the kidneys and contain an adrenal cortex and medulla. The cortex secretes corticosteroids like mineralocorticoids and glucocorticoids. Aldosterone is the main mineralocorticoid produced in the zona glomerulosa, while cortisol is the primary glucocorticoid from the zona fasciculata. Cortisol regulates blood glucose and sodium/potassium balance. The document also outlines the functions of aldosterone in increasing sodium reabsorption and potassium secretion in the kidneys.
Examville.com is a website that provides online practice tests, live classes, tutoring, study guides, Q&A, and premium content to help people prepare for exams. The document then discusses the key parts and features of the axial skeleton, including the vertebral column, ribs, sternum, and thorax. It also lists the bones and structures that make up the vertebral column, ribs, and sternum. The summary concludes by mentioning that joining Examville.com is free.
The document provides information about the muscular, circulatory, and lymphatic systems of the human body. It describes the key functions and components of each system. The muscular system section explains the different muscle types and how muscles are named and organized in the body. The circulatory system section outlines the heart structure and function and describes the arterial, venous, and capillary systems. The lymphatic system transports lymph and provides defense functions.
The document summarizes the structure and function of the integumentary system. It describes the two main layers of the skin - the epidermis and dermis - as well as additional structures like hair, nails, and glands. The skin provides protection, regulates temperature and fluid balance, and plays a role in sensation, blood storage, and metabolism. Key cell types in the epidermis include keratinocytes, melanocytes, Langerhans cells, and Merkel cells.
The document provides information about the structure and function of the human heart. It is divided into sections on the right heart and left heart. The right heart receives deoxygenated blood from the body and pumps it to the lungs. The left heart receives oxygenated blood from the lungs and pumps it out to the body through the aorta to support the systemic circulation. Key components include the right and left atria and ventricles, tricuspid and mitral valves, and major blood vessels like the vena cavae, pulmonary artery and veins, and aorta.
The document provides information about the structure and function of the human heart. It is divided into sections on the right heart and left heart. The right heart receives deoxygenated blood from the body and pumps it to the lungs. The left heart receives oxygenated blood from the lungs and pumps it out to the body through the aorta to support the systemic circulation. Key components include the right and left atria and ventricles, tricuspid and mitral valves, and major blood vessels like the vena cavae, pulmonary artery and veins, and aorta.
The document provides information about the structure and function of the human heart. It is divided into sections on the right heart and left heart. The right heart receives deoxygenated blood from the body and pumps it to the lungs. The left heart receives oxygenated blood from the lungs and pumps it out to the body through the aorta to sustain the circulatory system. Key components include the right and left atria and ventricles, tricuspid and mitral valves, and major blood vessels like the vena cavae, pulmonary artery and veins, and aorta.
The human heart is a muscular organ that pumps blood through the body. It is divided into four chambers - two atria that receive blood and two ventricles that pump blood out. The right side receives deoxygenated blood from the body and pumps it to the lungs. The left side receives oxygenated blood from the lungs and pumps it out to the body through the aorta. Valves control the direction of blood flow between the chambers and vessels. The heart is a vital organ that circulates blood continuously through two circuits - pulmonary circulation to the lungs and systemic circulation to the body.
The document describes the anatomy and structures of the heart. It discusses:
- The heart is surrounded by the pericardium, a double-walled sac that has an outer fibrous layer and inner serous layers separated by fluid.
- The heart has four chambers - two upper atria that receive blood and two lower ventricles that pump blood out. Blood flows through valves between the chambers.
- The heart wall has three layers - the outer epicardium, middle muscular myocardium, and inner endothelial endocardium.
- The heart is supplied by the right and left coronary arteries and drains into the coronary sinus vein.
- Nerves from the autonomic nervous system
The heart is a hollow, muscular organ located slightly left of center in the chest. It is surrounded by three layers of tissue - the outer fibrous pericardium, middle muscular myocardium, and inner endothelial endocardium. The heart is divided into four chambers - right atrium, right ventricle, left atrium, and left ventricle - with valves that ensure one-way blood flow. Deoxygenated blood enters the right atrium from the body and is pumped to the lungs via the right ventricle. Oxygenated blood returns to the left atrium from the lungs and is pumped back out to the body by the left ventricle.
The document summarizes the anatomy of the pericardium and heart. It describes the pericardium as a fibroserous sac that encloses the heart. It then discusses the layers of the pericardium - the fibrous pericardium and serous pericardium with its parietal and visceral layers. It also describes the surfaces, chambers, valves and conducting system of the heart.
The document describes the structure and function of the heart and circulatory system. It discusses the major veins that return deoxygenated blood to the right atrium, such as the superior and inferior vena cava. It also describes the four chambers of the heart, including the right and left atria that receive blood and the right and left ventricles that pump blood to the lungs and body. The valves such as the tricuspid and bicuspid valves prevent backflow of blood through the heart.
The document provides an overview of the human circulatory system, including:
- The heart pumps blood through vessels in a double circulatory system, with the pulmonary and systemic circuits.
- The heart has four chambers, with the right atrium and ventricle pumping to the lungs and the left pumping to the body. It is located in the mediastinum.
- Blood flows through one-way valves between the atria and ventricles, and into the pulmonary trunk and aorta.
- The cardiac conduction system coordinates heart chamber contractions for efficient blood flow.
The pericardium is a fibroserous sac that encloses and protects the heart. It has two layers - a fibrous outer layer and a serous inner layer. The heart has four chambers - right and left atria which receive blood, and right and left ventricles which pump blood out. Each chamber has a specific structure and function in the circulation. The heart also has a conducting system that generates electrical signals to coordinate contractions and pumping of the heart.
This presentation will help you to get to known about the human heart in very much clear way. It will help you alot in making your concepts clear regarding the human heart and it's functioning.
The document summarizes the anatomy of the cardio-vascular system of goats. It describes the heart which has four chambers - right atrium, right ventricle, left atrium and left ventricle. Blood enters the right atrium from the vena cava and is pumped to the right ventricle before entering the lungs via the pulmonary artery. Oxygenated blood returns from the lungs to the left atrium and is pumped to the left ventricle and then to the rest of the body via the aorta. It also outlines the major blood vessels including the aorta, anterior vena cava and posterior vena cava.
The heart is a hollow muscular organ responsible for pumping blood through the circulatory system. It has four chambers: right atrium, right ventricle, left atrium, and left ventricle. The heart is surrounded by membranes and has three layers - epicardium, myocardium, and endocardium. It is located in the chest cavity and pumps oxygenated blood received from the lungs through the left side of the heart to the entire body. The heart has four valves that prevent backflow of blood - tricuspid valve, pulmonary valve, mitral valve, and aortic valve.
The primitive blueprint for the heart and circulatory system emerged with the arrival of the third mesodermal germ layer in bilaterians. Since then, hearts in animals have evolved from a single layered tube to a multiple chambered heart in due course of time.
The document provides an overview of the anatomy of the heart, including its chambers, surfaces, borders, valves, conduction system, and blood supply. Some key points:
- The heart has 4 chambers - right and left atria, right and left ventricles. It is located in the mediastinum and covered by the pericardium.
- It has 3 surfaces - sternocostal, diaphragmatic, left surface - and 3 borders - right, left, inferior.
- The 4 valves are the tricuspid, mitral, aortic and pulmonary valves.
- The conduction system initiates and conducts electrical impulses, starting from the sinoatrial
The document provides details on the anatomy of the heart, including its chambers, valves, blood vessels, and conducting system. Some key points:
- The heart has four chambers - two atria and two ventricles. It is located slightly left of center in the chest.
- The right side receives deoxygenated blood from the body and pumps it to the lungs. The left side receives oxygenated blood from the lungs and pumps it out to the body.
- Valves separate the chambers and ensure one-way blood flow. The septum divides the left and right sides.
- The conducting system generates electrical signals that coordinate rhythmic contractions of the atria and ventricles.
Anatomy of heart dr nikunj shekhada (mbbs,ms gen surg ,dnb cts SR) 11 6-18DR NIKUNJ SHEKHADA
The document provides an overview of the anatomy of the heart. It describes the heart as a hollow muscular organ located in the middle mediastinum behind the sternum. The heart has four chambers - two atria which receive blood and two ventricles which pump blood out. It notes the positions of structures like the cardiac apex. It then describes in detail the layers of the heart wall, the structure of the atria and ventricles, surrounding tissues like the pericardium, valves, blood vessels including the coronary arteries and veins, and the electrical conduction system.
The heart is a muscular organ that pumps blood through the circulatory system. It has four chambers - two upper atria and two lower ventricles. The right side receives deoxygenated blood and pumps it to the lungs, while the left side receives oxygenated blood and pumps it out to the body. Valves prevent backflow between chambers. The heart is surrounded by membranes and layers including the pericardium. It is located in the chest cavity and has distinct surfaces and structures that allow it to efficiently circulate blood throughout the body.
The document provides information about SAT and ACT prep courses. Day one of the SAT prep course focuses on general test strategies and tips for the verbal and math sections, followed by practice. Day two involves taking full practice tests, self-scoring, and analyzing results. Sample SAT questions and strategies for answering different types of questions are also outlined. Information on test dates, costs, and scoring is provided for both the SAT and ACT.
This document provides information about preparing for the SAT math section. It discusses general SAT information like scoring, content, and what to bring. Key math facts and concepts are reviewed, like types of equations, symbols, and ratios. Several practice problem types are covered, such as graphs and functions. Websites for additional practice are provided, along with test dates and tips for students and parents. The presenters provide their contact information and background.
The document provides information about changes being made to the Math section of the SAT. It discusses removing quantitative comparisons and focusing more on math reasoning and real-world problems. It outlines the specific math content areas that will be covered, including algebra, functions, geometry, statistics, and probability. It also describes the types of questions that will be asked, such as grid-in questions, and the use of calculators.
1. If two sides of a triangle are congruent, then the angles opposite those sides are also congruent.
2. The largest side of a triangle is always opposite the largest angle.
3. When using the Pythagorean theorem, you should draw a right triangle with the hypotenuse across from the right angle.
The PSAT/NMSQT is co-sponsored by the College Board and National Merit Scholarship Corporation. The document explains how to understand a PSAT/NMSQT score report, including sections for critical reading, math, and writing scores. It provides information on national percentile ranks, estimated SAT scores, reviewing answers, and suggestions for improving skills in areas where a student scored lower. The report also includes details about National Merit Scholarship programs and recommended educational plans based on a student's intended college major.
1. This document provides a list of math facts and concepts that are important to know for the SAT Math section. It includes topics like slope, percent problems, geometry formulas, and working with fractions, decimals, and integers.
2. Students are given examples to practice these concepts, with problems about solving equations, simplifying expressions, finding slopes of lines, and using the Pythagorean theorem.
3. The document emphasizes remembering formulas like the slope formula, properties of parallel and perpendicular lines, and being able to identify key information in word problems and figures related to math concepts on the SAT.
Examville.com provides online educational resources like practice tests, live classes, tutoring, study guides, and premium content to help students prepare for exams. The document then reviews carbohydrates, including their classification, structures, functions, examples like monosaccharides, disaccharides, and polysaccharides. It also discusses topics like glycolysis, the citric acid cycle, and the biogenic roles of these metabolic pathways.
The document provides an overview of the history and approaches to the study of human anatomy. It discusses how anatomy was first formally studied in ancient Egypt and Greece. Key figures like Aristotle, Vesalius, and William Harvey contributed seminal works and discoveries. The document also outlines the regional, systemic, and clinical approaches to anatomy. It defines important anatomical terminology and concepts like planes, sections, and anatomical positions. Finally, it provides details on the structure and functions of skin and fascia.
The document provides detailed information about the anatomy of the head and neck region. It describes the bones that make up the skull, including the neurocranium and facial skeleton. It also discusses landmarks on the anterior, lateral, and posterior aspects of the skull. Additionally, it summarizes the muscles of facial expression and mastication, nerves and vasculature of the head and neck region, as well as structures located in the infratemporal fossa.
Examville is a website that provides online practice tests, live classes, tutoring, study guides, Q&A, and premium content to help students prepare for exams. Users can access these resources for free by creating an account on the site. The site aims to help students by offering various tools and materials to improve exam performance and learning outcomes.
The document provides an overview of various cardiac medications, including their classifications, mechanisms of action, indications, and dosages. It focuses on inotropes like digoxin, chronotropes like atropine, antianginal drugs like nitroglycerin, antidysrhythmics/antiarrhythmics in the four main classes, and discusses specific drugs like quinidine, lidocaine, and flecainide. It includes questions and answers related to calculating digoxin doses and identifying positive inotropes and the preferred route for nitroglycerin during angina attacks.
The nasal cavity is divided by the nasal septum into left and right cavities. Each cavity contains 4 passages formed by the nasal conchae: the sphenoethmoidal recess, superior meatus, middle meatus, and inferior meatus. The nasal cavities are lined with mucous membrane and contain paranasal sinuses. Epistaxis or nosebleeds can occur due to various causes like trauma, infections, or anatomical abnormalities. Posterior nosebleeds from Woodruff's plexus are difficult to treat due to its inaccessible location.
The document discusses the three meninges - the outer dura mater, middle arachnoid mater, and inner pia mater. It describes the layers of the dura mater, venous sinuses within the dura mater including the superior sagittal sinus, transverse sinus and sigmoid sinus, arteries that supply the dura mater, and the subarachnoid space between the arachnoid mater and pia mater. It also mentions the choroid plexus which is involved in cerebrospinal fluid production.
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2. Human Heart
HEART
is a squared
shape, muscular
organ responsible
for pumping blood
through the blood
vessels by
repeated, rhythmic
contractions, or a
similar structure in
annelids,
mollusks, and
arthropods
3. The Heart is divided into two
Right heart
Left heart
4. Right heart
is a term used to refer collectively to the right atrium and
right ventricle of the heart; occasionally, this term is intended to
reference the right atrium, right ventricle, and the pulmonary trunk
collectively.
The right atrium receives deoxygenated systemic blood from the
superior and inferior vena cavae. The blood is then pumped through
the tricuspid valve into the right ventricle, which in turn pumps the
blood through the pulmonary valve into the pulmonary artery.
Vena cavae, Coronary sinus
→ Right atrium (auricle, fossa ovalis, limbus of fossa
ovalis, crista terminalis, valve of the inferior vena cava,
valve of the coronary sinus)
Tricuspid valve
→ Right ventricle (conus arteriosus, moderator
band/septomarginal trabecula)
Pulmonary valve
→ Pulmonary Artery
→ Pulmonary Circulation
5. The superior and inferior vena
Venae cavae cava are collectively called the
venae cavae. They are the veins
that return de-oxygenated blood
from the body into the heart.
They both empty into the right
atrium.
The superior vena cava (or
anterior)
is above the heart, and
forms from a convergence of the
left and right brachiocephalic
veins that contain blood from
the head and the arms. The vena
cavae carry deoxygenated blood
from the body to the right atrium
of the heart.
The venae cavae is the largest
blood vessel in the heart.
The inferior vena cava (or
posterior vena cava)
travels up alongside the
abdominal aorta with blood from
the lower part of the body.
6. Coronary Sinus
Coronary Sinus is a collection of veins
joined together to form a large
vessel that collects blood from
the myocardium of the heart. It
is present in humans and other
animals.
Location
It is located between the left
atrium and ventricle on the
posterior surface of the heart.
It runs transversely in the
groove between the left atrium
and ventricle on the posterior
surface of the heart.
The coronary sinus orifice
(opening) is just superior to the
septal leaflet of the tricuspid
valve. The coronary sinus orifice
is also known as the ostium of
the coronary sinus
7. Right Atrium
Right Atrium (in older texts
termed the "right auricle")
is one of four chambers (two
atria and two ventricles) in the
human heart. It receives de-
oxygenated blood from the superior
and inferior vena cavae and the
coronary sinus, and pumps it into
the right ventricle through the
tricuspid valve.
Sinoatrial node (SAN)
is located within this chamber
next to the vena cava. This is a
group of pacemaker cells which
spontaneously depolarise to create
an Action Potential. The cardiac
action potential then spreads across
both atria causing them to contract
forcing the blood they hold into their
corresponding ventricles.
8. Right Ventricle
Right Auricular Appendix
Fossa Ovalis
Limbus of Fossa Ovalis
Crista Terminalis
Valve of the Inferior Vena Cava
Valve of the Coronary Sinus
9. Right Auricular Appendix
Right auricular appendix
(right auricula, right
auricle) is a small conical
muscular pouch attached
to the right atrium of the
heart. Its margins present
a dentated edge. It projects
from the upper and front
part of the sinus forward
and toward the left side,
overlapping the root of the
aorta.
10. Fossa Ovalis (heart)
Found in the right
atrium of the heart, the
Fossa Ovalis is an
embryonic remnant of
the foramen ovale,
which normally closes
shortly after birth.
Failure of the foramen
ovale to close results
in a disorder known as
patent foramen ovale.
11. Limbus of Fossa Ovalis
Limbus of fossa ovalis
(annulus ovalis)
is the prominent oval
margin of the fossa ovalis.
It is most distinct above
and at the sides of the fossa;
below, it is deficient.
A small slit-like valvular
opening is occasionally found,
at the upper margin of the fossa,
leading upward beneath the
limbus, into the left atrium; it is
the remains of the fetal aperture
between the two atria.
12. Crista Terminalis
In the development of
the human heart, the right
horn and transverse
portion of the sinus
venosus ultimately
become incorporated with
and form a part of the adult
right atrium, the line of
union between it and the
right auricle being
indicated in the interior of
the atrium by a vertical
crest, the crista terminalis
of His (Wilhelm His, Jr.).
13. Valve of the Inferior Vena Cava
The valve of the
inferior vena cava
(eustachian valve) serves
to direct the blood from
that vessel through the
foramen ovale into the left
atrium.
The eustachian valve
is the valve at the distal
end of the inferior vena
cava the passes blood
from the lower extremities
into the Right Atrium of the
heart
14. Valve of the Coronary Sinus
The valve of the
coronary sinus (Thebesian
valve) is a semicircular
fold of the lining
membrane of the atrium, at
the orifice of the coronary
sinus. The valve may vary
in size, or be completely
absent.
It may prevent the
regurgitation of blood into
the sinus during the
contraction of the atrium.
This valve may be
double or it may be
cribriform.
15. Tricuspid Valve
Tricuspid valve
is on the right side of
the heart, between the
right atrium and the right
ventricle. The normal
tricuspid valve usually has
three leaflets and three
papillary muscles.
16. Tricuspid Valve
The largest cusp is interposed between the
atrioventricular orifice and the conus arteriosus and is
termed the anterior or infundibular cusp.
A second, the posterior or marginal cusp, is in relation
to the right margin of the ventricle.
A third, the medial or septal cusp, to the ventricular
septum.
The tricuspid valve prevents the blood from returning
to the right atrium when the right ventricle contracts
***** The tricuspid valve also opens and
closes at periods of time making the blood
flow through from the right atrium to the
right ventricle*****
17. Right Ventricle
Conus Arteriosus
Moderator Band/Septomarginal
Trabecula
18. Right Ventricle
Right ventricle
is one of four chambers
(two atria and two
ventricles) in the human
heart. It receives de-
oxygenated blood from the
right atrium via the
tricuspid valve, and pumps
it into the pulmonary artery
via the pulmonary valve.
It is triangular in form,
and extends from the right
atrium to near the apex of
the heart.
19. Conus Arteriosus
Conus Arteriosus
is a conical pouch formed
from the upper and left angle of
the right ventricle, from which
the pulmonary artery arises.
A tendinous band, which
may be named the tendon of the
conus arteriosus, extends
upward from the right
atrioventricular fibrous ring and
connects the posterior surface
of the conus arteriosus to the
aorta. This is also called the
infundibulum, and it is the
entrance from the right ventricle
into the pulmonary artery and
pulmonary trunk. The wall of the
infundibulum is smooth.
20. Septomarginal trabecula
Septomarginal (or moderator band)
Trabecula is a muscular band of heart
tissue found in the right ventricle. It
is well-marked in sheep and some
other animals, and frequently
extends from the base of the
anterior papillary muscle to the
ventricular septum.
From its attachments it was
thought to prevent overdistension
of the ventricle, and was named the
"moderator band". However, more
recent research has indicated that it
is more properly considered part of
the electrical conduction system of
the heart, and in that capacity it is
called the "septomarginal
trabecula". The TA name is
"trabecula septomarginalis".
The moderator band is often
used by radiologists to more easily
identify the right ventricle in
prenatal ultrasound.
21. Pulmonary Valve
Pulmonary Valve
is the semilunar valve of the
heart that lies between the right
ventricle and the pulmonary artery
and has three cusps. Similar to the
aortic valve, the pulmonic valve
opens in ventricular systole, when
the pressure in the right ventricle
rises above the pressure in the
pulmonary artery. At the end of
ventricular systole, when the
pressure in the right ventricle falls
rapidly, the pressure in the
pulmonary artery will close the
pulmonic valve.
23. Pulmonary Artery
Pulmonary arteries carry
blood from the heart to the lungs.
They are the only arteries (other
than umbilical arteries in the
fetus) that carry deoxygenated
blood.
In the human heart, the
pulmonary trunk (pulmonary
artery or main pulmonary artery)
begins at the base of the right
ventricle. It is short and wide -
approximately 5 cm (2 inches) in
length and 3 cm (1.2 inches) in
diameter. It then branches into
two pulmonary arteries (left and
right), which deliver deoxygenated
blood to the corresponding lung.
24. Pulmonary Circulation
Pulmonary Circulation
is the portion of the cardiovascular system which carries oxygen-
depleted blood away from the heart, to the lungs, and returns oxygenated
blood back to the heart. The term is contrasted with systemic circulation.
Oxygen-depleted blood from the body leaves the right heart through the
pulmonary arteries, which carry it to the lungs, where red blood cells release
carbon dioxide and pick up oxygen during respiration. The oxygenated blood
then leaves the lungs through the pulmonary veins, which return it to the left
heart, completing the pulmonary cycle. The blood is then distributed to the
body through the systemic circulation before returning again to the
pulmonary circulation.
25. Left heart
is a term used to refer collectively to the left atrium and lef
ventricle of the heart; occasionally, this term is intended to reference
the left atrium, left ventricle, and the aorta collectively.
The left atrium receives oxygenated pulmonic blood from the
pulmonary veins. The blood is then pumped through the mitral valve
into the left ventricle, which in turn pumps the blood through the aortic
valve into the aorta.
The left side of the heart is thicker than the right because of the
requirement to pump blood from the left throughout the body, as
opposed to the right side pumping only through the lungs.
Pulmonary veins
Left atrium
Left Auricular Appendix
Mitral valve
Left ventricle
Aortic valve
Aortic sinus
Aorta
Systemic circulation
26. Pulmonary Veins
The pulmonary veins carry
oxygen-rich blood from the
lungs to the left atrium of the
heart. They are the only veins in
the post-fetal human body that
carry oxygenated (red) blood.
• The pulmonary veins return the
oxygenated blood from the
lungs to the left atrium of the
heart. They are four in number,
two from each lung, and are
destitute of valves. They are
• Right Inferior
• Right Superior
• Left Inferior
• Left Superior
27. Left Atrium
Left atrium
is one of the four chambers
in the human heart. It receives
oxygenated blood from the
pulmonary veins, and pumps it
into the left ventricle.
Blood is pumped through
the left atrioventricular orifice,
which contains the mitral valve.
A normal left atrium may be up
to 5.5cm in maximum diameter;
any larger than this is a sign of
cardiac failure. This may occur
in cases of mitral regurgitation.
28. Left Auricular Appendix
Left Auricular Appendix
(left auricula, left
auricle)
is a conical muscular
pouch connected to the left
atrium of the heart. It is
somewhat constricted at its
junction with the principal
cavity; it is longer, narrower,
and more curved than the right
auricular appendix, and its
margins are more deeply
indented.
It is directed forward and
toward the right and overlaps
the root of the pulmonary artery.
29. Mitral Valve
Mitral valve (also known
as the bicuspid valve or
left atrioventricular
valve)
is a dual flap (bi = 2) valve
in the heart that lies between the
left atrium (LA) and the left
ventricle (LV). In Latin, the term
mitral means shaped like a
miter, or bishop's cap. The
mitral valve and the tricuspid
valve are known collectively as
the atrioventricular valves
because they lie between the
atria and the ventricles of the
heart and control flow.
30. Left ventricle
The left ventricle is
one of four chambers
(two atria and two
ventricles) in the human
heart. It receives
oxygenated blood from
the left atrium via the
mitral valve, and pumps
it into the aorta via the
aortic valve.
The left ventricle is
longer and more conical
in shape than the right,
and on transverse
section its concavity
presents an oval or
nearly circular outline. It
forms a small part of the
sternocostal surface and
a considerable part of
the diaphragmatic
surface of the heart; it
also forms the apex of
the heart.
31. Aortic Valve
Aortic valve
is one of the valves of the
heart. It lies between the left
ventricle and the aorta.
Morphology
The aortic valve has three
cusps. These cusps are half
moon shaped hence also called
aortic semilunar valve. Each
cusp has a small swelling in the
center called the nodule.
Dilatation of the wall of the aorta
behind these cusps is called
aortic sinus. When the aortic
valve is open, the normal size of
the orifice is 3-4 cm² in adults.
32. Aortic Sinus
An aortic sinus is one of the anatomic dilations of the
ascending aorta, which occurs just above the aortic valve.
There are generally three aortic sinuses, the left, the right and the
posterior.
• The left aortic sinus gives rise to the left coronary artery.
• The right aortic sinus gives rise to the right coronary artery.
• Usually, no vessels arise from the posterior aortic sinus, which
is therefore known as the non-coronary sinus.
33. Aorta
The aorta (generally
pronounced [eɪˈɔːtə] or
"ay-orta") is the largest
artery in the human body,
originating from the left
ventricle of the heart and
bringing oxygenated blood
to all parts of the body in
the systemic circulation.
The course of the Aorta
The aorta is usually divided
into five
segments/sections:
• Ascending aorta
• Arch of aorta
• Descending aorta
• Thoracic aorta
• Abdominal aorta
34. Ascending aorta, Arch of aorta, Descending aorta
• Ascending Aorta —
the section between the
heart and the arch of aorta
• Arch of Aorta — the
peak part that looks
somewhat like an inverted
"U"
• Descending Aorta —
the section from the arch
of aorta to the point where
it divides into the common
iliac arteries
35. Thoracic aorta
Thoracic aorta
is contained in the
posterior mediastinal cavity.
It begins at the lower
border of the fourth thoracic
vertebra where it is
continuous with the aortic
arch, and ends in front of the
lower border of the twelfth at
the aortic hiatus in the
diaphragm.
At its commencement, it
is situated on the left of the
vertebral column; it
approaches the median line
as it descends; and, at its
termination, lies directly in
front of the column.
36. Abdominal Aorta
Abdominal Aorta
is a large artery in
the abdominal cavity.
As part of the aorta, it
is a direct continuation
of descending aorta
(of the thorax).
37. Systemic Circulation
Systemic Circulation
is the portion of the cardiovascular
system which carries oxygenated
blood away from the heart, to the body,
and returns deoxygenated blood back
to the heart. The term is contrasted
with pulmonary circulation.
Oxygenated blood from the lungs
leaves the left heart through the aorta,
from where it is distributed to the
body's organs and tissues, which
absorb the oxygen, through a complex
network of arteries, arterioles, and
capillaries. The deoxygenated blood is
then collected by venules, from where
it flows first into veins, and then into
the inferior and superior venae cavae,
which return it to the right heart,
completing the systemic cycle. The
blood is then re-oxygenated through
the pulmonary circulation before
returning again to the systemic
circulation.
38. Layers of the Heart
1.) Pericardium
1.1.)Sinus
a.) Oblique Sinus
b.) Transverse Sinus
2.) Epicardium
3.) Myocardium
4.) Endocardium
5.) Cardiac skeleton
5.1.) Fibrous trigone
5.2.) Fibrous rings
39. Pericardium
is a double-walled sac that contains the heart and the roots of the great
vessels.
Layers of Pericardium
A.) Fibrous Pericardium
is the most superficial layer. It is a dense connective tissue,
protecting the heart, anchoring it to the surrounding walls, and
preventing it from overfilling with blood. It is continuous with the outer
adventitial layer of the neighboring great blood vessels.
B.) Serous Pericardium
is deep to the fibrous pericardium. It contains two layers, both of
which function in lubricating the heart to prevent friction from
occurring during heart activity.
40. Pericardial Sinuses
The cul-de-sac enclosed between the limbs of the
inverted U of the venous mesocardium lies behind the left
atrium and is known as the Oblique Sinus.
The passage between the venous and arterial
mesocardia—i.e., between the aorta and pulmonary artery
in front and the atria behind—is termed the Transverse
Sinus.
41. Epicardium
describes the outer layer of heart tissue (from Greek; epi-
outer, cardium heart). When considered as a part of the
pericardium, it is the inner layer, or visceral pericardium.
Its largest constituent is connective tissue and functions as
a protective layer. The visceral pericardium apparently
produces the pericardial fluid, which lubricates motion between
the inner and outer layers of the pericardium.
During ventricular contraction, the wave of depolarization
moves from endocardial to epicardial surface.
42. Myocardium
is the muscular tissue of the heart.
Relationship to other layers
The other tissues of the heart are:
The Endocardium (inner lining, effectively a specialised endothelium)
The Epicardium (a connective tissue layer around the heart with a
serous surface. It may be considered as the inner (visceral) layer of the
pericardium).
Composition
The myocardium is composed of specialized cardiac muscle cells
with an ability not possessed by muscle tissue elsewhere in the body.
Cardiac muscle, like other muscles, can contract, but it can also
conduct electricity, like nerves.
The blood supply of the myocardium is by the coronary arteries.
43. Endocardiumlayer of tissue that lines
In the heart, the endocardium is the innermost
the chambers of the heart. Its cells, embryologically and biologically, are
similar to the endothelial cells that line blood vessels.
The endocardium overlies the much more voluminous myocardium, the
muscular tissue responsible for the contraction of the heart. The outer layer
of the heart is termed epicardium and the heart is surrounded by a small
amount of fluid enclosed by a fibrous sac called the pericardium.
Function
Recently, it has become evident that the endocardium, which is
primarily made up of endothelial cells, controls myocardial function. This
modulating role is separate from the homeometric and heterometric
regulatory mechanisms that control myocardial contractility. Moreover, the
endothelium of the myocardial (heart muscle) capillaries, which is also
closely appositioned to the cardiomyocytes (heart muscle cells) are involved
in this modulatory role. Thus, the cardiac endothelium (both the endocardial
endothelium and the endothelium of the myocardial capillaries) controls the
development of the heart in the embryo as well as in the adult, for example
during hypertrophy. Additionally, the contractility and electrophysiological
environment of the cardiomyocyte are regulated by the cardiac endothelium.
The endocardial endothelium may also act as a kind of blood-heart
barrier (analogous to the blood-brain barrier), thus controlling the ionic
composition of the extracellular fluid in which the cardiomyocytes bathe.
44. Cardiac skeleton
Cardiac skeleton (sometimes called "fibrous skeleton of the heart") refers to
the structure of dense connective tissue in the heart that separates the atria
from the ventricles.
It is not a "true" skeleton, but it does provide structure and support for
the heart, as well as isolating the electric charges that go through the heart.
The left atrioventricular ring is closely connected, by its right margin,
with the aortic arterial ring; between these and the right atrioventricular ring
is a triangular mass of fibrous tissue, the fibrous trigone, which represents
the os cordis seen in the heart of some of the larger animals, as the ox and
elephant.
The right and left fibrous rings of heart (anulus fibrosus cordis)
surround the atrioventricular and arterial orifices, and are stronger upon the
left than on the right side of the heart. The right fibrous ring is known as the
anulus fibrosus dexter cordis, and the left is known as the anulus fibrosus
sinister cordis
47. Musculi Pectinati
In the right atrium,
behind the crest the
internal surface of the
atrium is smooth, while in
front of it the muscular
fibers of the wall are
raised into parallel ridges
resembling the teeth of a
comb, and hence named
the musculi pectinati
(pectinate muscles).
49. Interventricular Septum
Portions
Interventricular septum (or
ventricular septum, or during
development septum inferius) is The greater portion of it is
the stout wall separating the lower thick and muscular and constitutes
chambers (the ventricles) of the the muscular ventricular septum.
heart from one another.
Its upper and posterior part,
The ventricular septum is which separates the aortic
directed obliquely backward and to vestibule from the lower part of the
the right, and is curved with the right atrium and upper part of the
convexity toward the right ventricle: right ventricle, is thin and fibrous,
its margins correspond with the and is termed the membranous
anterior and posterior longitudinal ventricular septum (septum
sulci. membranaceum).
50. Trabeculae Carneae
The trabeculae carneae (columnae carneae) are
rounded or irregular muscular columns which project from the
whole of the inner surface of the ventricle, with the exception of
the conus arteriosus.
They are of three kinds:
1.) Some are attached along their entire length on one side and merely
form prominent ridges,
2.) Others are fixed at their extremities but free in the middle,
3.) While a third set (musculi papillares) are continuous by their bases with
the wall of the ventricle, while their apices give origin to the chordæ
tendineæ which pass to be attached to the segments of the tricuspid valve.
51. Chordae Tendinae
The chordae
tendineae, or heart
strings, are cord-like
tendons that connect the
papillary muscles to the
tricuspid valve and the
mitral valve in the heart.
When the right
ventricle of the heart
contracts, the blood
pressure pushes the
tricuspid valve which closes
and prevents a backflow of
blood into the right atrium.
The chordae tendineae
prevents the flaps from
being everted into the right
atrium. Similarly, these
cord-like tendons hold in
position other flaps like the
bicuspid or mitral valve.
52. Papillary Muscle
Papillary muscles of
the heart serve to limit
the movements of the
mitral and tricuspid
valves. These muscles
contract to tighten the
chordae tendineae,
which in turn prevent
inversion. This occurs
in response to
pressure gradients.
Instead they brace the
valves against the high
pressure, preventing
regurgitation of
ventricular blood back
into the atrial cavities.
53. Heart Valves
Heart valves are
valves in the heart that
maintain the
unidirectional flow of
blood by opening and
closing depending on
the difference in
pressure on each side.
The mechanical
equivalent of the heart
valves would be the
reed valves.
54. Mitral Valve
The mitral valve
(also known as the
bicuspid valve or left
atrioventricular valve), is
a dual flap (bi = 2) valve in
the heart that lies between
the left atrium (LA) and the
left ventricle (LV). In Latin,
the term mitral means
shaped like a miter, or
bishop's cap. The mitral
valve and the tricuspid
valve are known
collectively as the
atrioventricular valves
because they lie between
the atria and the ventricles
of the heart and control
flow.
55. Tricuspid Valve
The tricuspid valve
is on the right side of the
heart, between the right
atrium and the right
ventricle. The normal
tricuspid valve usually has
three leaflets and three
papillary muscles.
Tricuspid valves may also
occur with two or four
leaflets, and the number
may change during life.
57. Aortic Valve
The aortic valve is one of the valves of the heart. It lies between the
left ventricle and the aorta.
Morphology
The aortic valve has three cusps. These cusps are half moon shaped
hence also called aortic semilunar valve. Each cusp has a small swelling in
the center called the nodule. Dilatation of the wall of the aorta behind these
cusps is called aortic sinus. When the aortic valve is open, the normal size of
the orifice is 3-4 cm² in adults.
Function & Physiology
During ventricular systole, pressure rises in the left ventricle. When the
pressure in the left ventricle rises above the pressure in the aorta, the aortic
valve opens, allowing blood to exit the left ventricle into the aorta. When
ventricular systole ends, pressure in the left ventricle rapidly drops. When
the pressure in the left ventricle decreases, the aortic pressure forces the
aortic valve to close. The closure of the aortic valve contributes the A2
component of the second heart sound (S2).
59. Pumonary Valve
is the semilunar valve of the heart that lies between the
right ventricle and the pulmonary artery and has three
cusps. Similar to the aortic valve, the pulmonic valve
opens in ventricular systole, when the pressure in the right
ventricle rises above the pressure in the pulmonary artery.
At the end of ventricular systole, when the pressure in the
right ventricle falls rapidly, the pressure in the pulmonary
artery will close the pulmonic valve.
The closure of the pulmonic valve contributes the P2
component of the second heart sound (S2). The right heart
is a low-pressure system, so the P2 component of the
second heart sound is usually softer than the A2
component of the second heart sound. However, it is
physiologically normal in some young people to hear both
components separated during inhalation.
60. Regions of The Heart
1.) Base
2.) Apex
3.) Grooves
a.) Coronary/atrioventricular
b.) Interatrial
c.) Anterior interventricula
d.) Posterior interventricular
4.) Surfaces
a.) Sternocostal
b.) Diaphragmatic
5.) Borders
a.) Right
b.) Left
61. Base of the Heart
Base of the heart, directed upward, backward,
and to the right, is separated from the fifth,
sixth, seventh, and eighth thoracic vertebræ by
the esophagus, aorta, and thoracic duct.
It is formed mainly by the left atrium, and,
to a small extent, by the back part of the right
atrium.
Somewhat quadrilateral in form, it is in
relation above with the bifurcation of the
pulmonary artery, and is bounded below by
the posterior part of the coronary sulcus,
containing the coronary sinus.
On the right it is limited by the sulcus
terminalis of the right atrium, and on the left by
the ligament of the left vena cava and the
oblique vein of the left atrium.
The four pulmonary veins, two on either
side, open into the left atrium, while the
superior vena cava opens into the upper, and
the anterior vena cava into the lower, part of
the right atrium.
62. Apex of the Heart
Apex of the heart
is the lowest superficial part of
the heart.
It is directed downward, forward,
and to the left, and is overlapped by
the left lung and pleura.
External Anatomy
It lies behind the fifth left
intercostal space, 8 to 9 cm. from the
mid-sternal line, slightly medial to the
midclavicular line.
Alternately, it can be found about
4 cm. below and 2 mm. to the medial
side of the left mammary papilla.
It's function is to pump blood to
left atruim
64. Coronary Sulcus
The atria of the heart are separated from
the ventricles by the coronary sulcus
(coronary groove, auriculoventricular
groove, atrioventricular groove); this
contains the trunks of the nutrient vessels
of the heart, and is deficient in front, where
it is crossed by the root of the pulmonary
artery.
65. Interatrial Groove
Interatrial groove, separating the two
atria, is scarcely marked on the
posterior surface, while anteriorly it is
hidden by the pulmonary artery and
aorta.
66. Anterior Interventricular Sulcus
The ventricles of the heart are separated
by two grooves, one of which, the anterior
longitudinal sulcus (or anterior
interventricular sulcus), is situated on the
sternocostal surface of the heart, close to its
left margin. The other groove separating the
ventricles is the posterior interventricular
sulcus.
67. Posterior Interventricular Sulcus
The ventricles are separated by two grooves,
one of which, the anterior longitudinal sulcus, is
situated on the sternocostal surface of the heart,
close to its left margin, the other posterior
longitudinal sulcus (posterior interventricular
sulcus, inferior interventricular groove), on the
diaphragmatic surface near the right margin.
In it run the posterior interventricular artery
and middle cardiac vein.
69. Sternocostal Surface of Heart
The sternocostal surface of the heart (anterior
surface of the heart) is directed forward, upward,
and to the left.
Its lower part is convex, formed chiefly by the
right ventricle, and traversed near its left margin
by the anterior longitudinal sulcus.
Its upper part is separated from the lower by
the coronary sulcus, and is formed by the atria; it
presents a deep concavity, occupied by the
ascending aorta and the pulmonary artery.
70. Diaphragmatic Surface of Heart
The diaphragmatic surface of the heart,
directed downward and slightly backward, is
formed by the ventricles, and rests upon the
central tendon and a small part of the left
muscular portion of the diaphragm.
It is separated from the base by the
posterior part of the coronary sulcus, and is
traversed obliquely by the posterior
longitudinal sulcus.
72. Right Border of Heart
Right margin of the heart (right border of
heart)
is long, and is formed by the right atrium above and the
right ventricle below.
The atrial portion is rounded and almost vertical; it is
situated behind the third, fourth, and fifth right costal
cartilages about 1.25 cm. from the margin of the sternum.
The ventricular portion, thin and sharp, is named the
acute margin; it is nearly horizontal, and extends from the
sternal end of the sixth right coastal cartilage to the apex
of the heart.
73. Left Margin of Heart
The left margin of heart (or obtuse margin) is shorter
than the right border of heart, full, and rounded: it
is formed mainly by the left ventricle, but to a
slight extent, above, by the left atrium.
It extends from a point in the second left
intercostal space, about 2.5 mm. from the sternal
margin, obliquely downward, with a convexity to
the left, to the apex of the heart.
74. Electrical conduction system of
the heart
The normal electrical conduction in the heart allows the
impulse that is generated by the sinoatrial node (SA node)
of the heart to be propagated to (and stimulate) the
myocardium (Cardiac muscle). After myocardium is
stimulated, it contracts. It is the ordered stimulation of the
myocardium that allows efficient contraction of the heart,
thereby allowing blood to be pumped throughout the body.
Cardiac Pacemaker
SA node
AV node
Bundle of His
Purkinje Fibers
75. Cardiac Pacemaker
The contractions of the heart are controlled by
chemical impulses, which fire at a rate which controls the
beat of the heart.
The cells that create these rhythmical impulses are
called pacemaker cells, and they directly control the heart
rate. Artificial devices also called pacemakers can be
used after damage to the body's intrinsic conduction
system to produce these impulses synthetically.
76. Sinoatrial node
Sinoatrial node (abbreviated SA node or
SAN, also called the sinus node)
is the impulse generating (pacemaker) tissue
located in the right atrium of the heart. It is a group
of cells positioned on the wall of the right atrium,
near the entrance of the superior vena cava. These
cells are modified cardiac myocytes. They possess
some contractile filaments, though they do not
contract.
77. Atrioventricular node
Atrioventricular node (abbreviated AV
node)
is an area of specialized tissue between the atria
and the ventricles of the heart, which conducts the
normal electrical impulse from the atria to the
ventricles. The AV node is also known as the
Aschoff-Tawara node.
The AV node receives two inputs from the atria:
posteriorly via the crista terminalis, and anteriorly
via the interatrial septum.
An important property that is unique to the AV
node is decremental conduction. This is the property
of the AV node that prevents rapid conduction to the
ventricle in cases of rapid atrial rhythms, such as
atrial fibrillation or atrial flutter.
78. Bundle of His
Bundle of His
is a collection of heart
muscle cells specialized for
electrical conduction that
transmits the electrical impulses
from the AV node (located
between the atria and the
ventricles) to the point of the
apex of the fascicular branches.
The fascicular branches then
lead to the Purkinje fibers which
innervate the ventricles, causing
the cardiac muscle of the
ventricles to contract at a paced
interval. These specialized
muscle fibres in the heart were
named after the Swiss
cardiologist Wilhelm His, Jr.,
who discovered them in 1893.
79. Purkinje Fibers
Purkinje fibers (or Purkyne tissue) are located in the
inner ventricular walls of the heart, just beneath the
endocardium. These fibers are specialized myocardial
fibers that conduct an electrical stimulus or impulse that
enables the heart to contract in a coordinated fashion.
Function
Purkinje fibers work with the sinoatrial node (SA node)
and the atrioventricular node (AV node) to control the heart
rate.
During the ventricular contraction portion of the
cardiac cycle, the Purkinje fibers carry the contraction
impulse from the left and right bundle branches to the
myocardium of the ventricles. This causes the muscle
tissue of the ventricles to contract and force blood out of
the heart — either to the pulmonary circulation (from the
right ventricle) or to the systemic circulation (from the left
ventricle).