The Heart
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The heart has contractile cells that produce powerful contractions to propel blood flow and a conducting system to control and coordinate the activity of the contractile cells. The conducting system is made up of nodal and conducting cells that initiate and distribute electrical impulses without contracting. It establishes the heart rate and ensures coordinated contraction of the atria and ventricles. The cardiac cycle involves systole where the heart contracts and diastole where it relaxes, moving blood from high to low pressure areas. Cardiac output, the amount of blood pumped per minute, is regulated by factors like blood volume, autonomic innervation, hormones, ion concentration and temperature.
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Cardiac output (The Guyton and Hall Physiology)
Cardiac output is the volume of blood pumped by each ventricle per minute. It is calculated as stroke volume multiplied by heart rate. Normal cardiac output is 5 liters per minute. Cardiac output is regulated by factors that influence stroke volume and heart rate. Stroke volume depends on end diastolic volume and end systolic volume. Heart rate is controlled by the autonomic nervous system, including the parasympathetic and sympathetic nerves, as well as the vasomotor center in the medulla. Parasympathetic stimulation decreases heart rate while sympathetic stimulation increases it.
Nervous system
the presentation describes the neurons, neuroglia, synapses, impulse transmission, neurotransmitters, meninges, ventricles, CSF, classification of nervous system, CNS - forebrain, midbrain, hindbrain, peripheral nervous system, somatic nervous system, autonomic nervous system, sympathetic nervous system, parasympathetic nervous system.
Nervous system
The nervous system is the chief controlling and coordinating system of the body. It consists of the brain, spinal cord, sensory organs, and nerves. The nervous system controls and regulates all voluntary and involuntary activities. It has three main functions: sensory function to collect information, integration to process sensory input and make decisions, and motor function to send responses to muscles and glands. The central nervous system includes the brain and spinal cord, which interpret sensory information. The peripheral nervous system includes nerves outside the brain and spinal cord that connect to sensory receptors.
Pns 7-
I apologize for any confusion, but I am an AI assistant created by Anthropic to be helpful, harmless, and honest.
Kidney (STRUCTURE AND FUNCTIONS) (: The Guyton and Hall physiology)
STRUCTURE AND FUNCTIONS OF KIDNEY
There are two kidneys in body , Rt & Lt, lying on post abdominal wall, outside peritoneal cavity.
There weight is aprx. 150 Gm and size is clenched fist.
On medial side, there is a region called hilum through which pass blood & lymphatic vessels, nerve fibers and ureterKidney is surrounded by a protective fibrous capsule.
Each kidney has two major zones, outer thick known as cortex and part known as medulla.
Medulla is divided into multiple cone shaped tissue masses called renal pyramid.
The base of pyramid begins at junction of cortex & medulla and terminates in papilla which projects into space of renal pelvis.
Renal pelvis is funnel shaped continuation of upper end of ureter.
1- Excretion of metabolic waste products such as urea, creatinine, uric acid, Bilirubin, hormones & drugs.
2-. ELIMINATE HARMFUL FOREIGN COMPOUNDS.
Such as toxins, drugs, heavy metals, pesticides.
3- Regulation of water & electrolyte balance to maintain normal homeostasis of body by re-absorption and adjustment of rate of excretion of various substances.
4- Regulation of Arterial Pressure.
*Long term regulation by excreting variable amounts of water and sodium
and
*short term by secreting vaso-active substance (renin).
Blood pressure & its regulation
1. Blood pressure is regulated through short, intermediate, and long-term control mechanisms. Short-term control is achieved through baroreceptor and chemoreceptor reflexes that sense changes in blood pressure and cardiac output.
2. Intermediate control is provided by the renin-angiotensin system, which causes vasoconstriction. Long-term control involves the renin-angiotensin-aldosterone system and hormones like vasopressin and atrial natriuretic peptide that regulate blood volume and vascular tone.
3. Local control of blood pressure is achieved through the actions of vasodilators like nitric oxide and vasoconstrictors like endothelin and angiotensin
Nervous system introduction
The nervous system is divided into the central nervous system (CNS) and peripheral nervous system (PNS). The CNS contains the brain and spinal cord, which receive sensory input, integrate information, and respond through motor output. The PNS includes the somatic and autonomic nervous systems. The somatic system connects the CNS to skeletal muscles and senses, while the autonomic system regulates involuntary functions through its sympathetic and parasympathetic divisions. Neurons are the basic functional units that conduct electrical signals, while neuroglia provide support and insulation to neurons.
coronary circulation
The coronary circulation supplies blood to the heart muscle. Blood flows through the right and left coronary arteries which branch from the aorta. Coronary blood flow increases during cardiac diastole as pressure in the intramural vessels is released, allowing more blood to enter the myocardium. Disruptions to coronary blood flow can cause myocardial ischemia, infarction, and angina pectoris due to insufficient oxygenation of heart tissue. Coronary occlusion from atherosclerosis is a leading cause of restricted blood flow and these downstream effects.
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Cardiac output (The Guyton and Hall Physiology)
Cardiac output is the volume of blood pumped by each ventricle per minute. It is calculated as stroke volume multiplied by heart rate. Normal cardiac output is 5 liters per minute. Cardiac output is regulated by factors that influence stroke volume and heart rate. Stroke volume depends on end diastolic volume and end systolic volume. Heart rate is controlled by the autonomic nervous system, including the parasympathetic and sympathetic nerves, as well as the vasomotor center in the medulla. Parasympathetic stimulation decreases heart rate while sympathetic stimulation increases it.
Nervous system
the presentation describes the neurons, neuroglia, synapses, impulse transmission, neurotransmitters, meninges, ventricles, CSF, classification of nervous system, CNS - forebrain, midbrain, hindbrain, peripheral nervous system, somatic nervous system, autonomic nervous system, sympathetic nervous system, parasympathetic nervous system.
Nervous system
The nervous system is the chief controlling and coordinating system of the body. It consists of the brain, spinal cord, sensory organs, and nerves. The nervous system controls and regulates all voluntary and involuntary activities. It has three main functions: sensory function to collect information, integration to process sensory input and make decisions, and motor function to send responses to muscles and glands. The central nervous system includes the brain and spinal cord, which interpret sensory information. The peripheral nervous system includes nerves outside the brain and spinal cord that connect to sensory receptors.
Pns 7-
I apologize for any confusion, but I am an AI assistant created by Anthropic to be helpful, harmless, and honest.
Kidney (STRUCTURE AND FUNCTIONS) (: The Guyton and Hall physiology)
STRUCTURE AND FUNCTIONS OF KIDNEY
There are two kidneys in body , Rt & Lt, lying on post abdominal wall, outside peritoneal cavity.
There weight is aprx. 150 Gm and size is clenched fist.
On medial side, there is a region called hilum through which pass blood & lymphatic vessels, nerve fibers and ureterKidney is surrounded by a protective fibrous capsule.
Each kidney has two major zones, outer thick known as cortex and part known as medulla.
Medulla is divided into multiple cone shaped tissue masses called renal pyramid.
The base of pyramid begins at junction of cortex & medulla and terminates in papilla which projects into space of renal pelvis.
Renal pelvis is funnel shaped continuation of upper end of ureter.
1- Excretion of metabolic waste products such as urea, creatinine, uric acid, Bilirubin, hormones & drugs.
2-. ELIMINATE HARMFUL FOREIGN COMPOUNDS.
Such as toxins, drugs, heavy metals, pesticides.
3- Regulation of water & electrolyte balance to maintain normal homeostasis of body by re-absorption and adjustment of rate of excretion of various substances.
4- Regulation of Arterial Pressure.
*Long term regulation by excreting variable amounts of water and sodium
and
*short term by secreting vaso-active substance (renin).
Blood pressure & its regulation
1. Blood pressure is regulated through short, intermediate, and long-term control mechanisms. Short-term control is achieved through baroreceptor and chemoreceptor reflexes that sense changes in blood pressure and cardiac output.
2. Intermediate control is provided by the renin-angiotensin system, which causes vasoconstriction. Long-term control involves the renin-angiotensin-aldosterone system and hormones like vasopressin and atrial natriuretic peptide that regulate blood volume and vascular tone.
3. Local control of blood pressure is achieved through the actions of vasodilators like nitric oxide and vasoconstrictors like endothelin and angiotensin
Nervous system introduction
The nervous system is divided into the central nervous system (CNS) and peripheral nervous system (PNS). The CNS contains the brain and spinal cord, which receive sensory input, integrate information, and respond through motor output. The PNS includes the somatic and autonomic nervous systems. The somatic system connects the CNS to skeletal muscles and senses, while the autonomic system regulates involuntary functions through its sympathetic and parasympathetic divisions. Neurons are the basic functional units that conduct electrical signals, while neuroglia provide support and insulation to neurons.
coronary circulation
The coronary circulation supplies blood to the heart muscle. Blood flows through the right and left coronary arteries which branch from the aorta. Coronary blood flow increases during cardiac diastole as pressure in the intramural vessels is released, allowing more blood to enter the myocardium. Disruptions to coronary blood flow can cause myocardial ischemia, infarction, and angina pectoris due to insufficient oxygenation of heart tissue. Coronary occlusion from atherosclerosis is a leading cause of restricted blood flow and these downstream effects.
Heart rate
Heart rate is the number of heartbeats per unit of time, usually per minute.
The heart rate is based on the number of contractions of the ventricles (the lower chambers of the heart).
Physiology of heart
The document summarizes the conduction system of the heart and the cardiac cycle. It discusses the following key points:
1. The heart's conduction system originates in specialized cardiac muscle cells called autorhythmic cells, which generate electrical impulses to initiate and coordinate heart contractions. The main structures of the conduction system are the sinoatrial node, atrioventricular node, bundle of His, and Purkinje fibers.
2. The cardiac cycle involves coordinated contraction and relaxation of the atria and ventricles. It begins with depolarization of the sinoatrial node, followed by atrial contraction, ventricular depolarization through the conduction system, ventricular contraction, and finally relaxation of both chambers.
Reticular formation in control of motor functions
The reticular formation is located in the central core of the brainstem and controls motor functions through direct and indirect projections. It contains two reticulospinal tracts - the medial and lateral tracts - that project to different regions of the spinal cord and modulate muscle tone, reflexes, posture, and movement. The reticular formation also projects to motor control centers in the brainstem, cerebellum, basal ganglia, and cortex to regulate skeletal muscle activity during facial expressions, voluntary movement, respiration, and maintaining balance and posture.
cardiac cycle
This document discusses cardiovascular physiology, beginning with an overview of the cardiac cycle and events in the cycle. It then covers determinants of myocardial performance including preload, afterload, contractility, and heart rate. Pressure-volume loops are introduced as a way to assess ventricular function. Physiological and pathological hypertrophy are compared. Key aspects covered include the Wiggers diagram, Frank-Starling mechanism, Anrep effect, Bowditch phenomenon, and formulas for calculating cardiac values.
Cardiac cycle physiology_4_dpt
The cardiac cycle describes the repeating sequence of events in the heart during one heartbeat. It begins with atrial systole which fills the ventricles with blood. This is followed by ventricular systole where the ventricles contract and eject blood out of the heart. The cardiac cycle is regulated by the heart's conduction system which coordinates the contractions of the atria and ventricles. It ensures the atria contract before the ventricles so blood is pumped efficiently through the heart and circulatory system with each heartbeat.
Blood pressure mechanism
Short-term regulation of blood pressure involves nervous and chemical mechanisms that act within seconds or minutes to control blood pressure. The nervous system regulates blood pressure by changing blood vessel diameter and heart rate through the sympathetic and parasympathetic nervous systems. Baroreceptors in the carotid sinus and aortic arch detect changes in blood pressure and stimulate reflex responses to return blood pressure to normal levels. Chemoreceptors sense oxygen and carbon dioxide levels and stimulate responses to maintain proper gas exchange in the lungs and tissues. If blood pressure drops severely, the brain triggers a central nervous system ischemic response to rapidly constrict blood vessels and raise blood pressure.
cardiac physiology
The document summarizes key aspects of cardiac physiology, including:
- The functions of the heart in generating blood pressure, routing blood flow, ensuring one-way flow, and regulating blood supply.
- The cardiac cycle and its phases of isovolumic contraction, ejection, isovolumic relaxation, and diastole.
- Factors that affect cardiac output including venous return, heart rate, contractility, and peripheral resistance.
- Key reflexes that regulate cardiac function such as the baroreceptor, chemoreceptor, and Bezold-Jarisch reflexes.
The Cardiovascular System
The document summarizes the anatomy and physiology of the cardiovascular system. It describes the location and structure of the heart, including its layers, chambers, and valves. It then discusses the cardiac conduction system, including the sinoatrial node which acts as the pacemaker, and how electrical signals cause coordinated heart contractions and relaxation. It concludes by defining cardiac output and some of the key factors that can influence it, such as heart rate, stroke volume, sympathetic tone, preload and afterload.
Autonomic nervous system
The autonomic nervous system (ANS) controls involuntary bodily functions and is divided into the sympathetic and parasympathetic nervous systems. The sympathetic system prepares the body for "fight or flight" through increased heart rate, breathing, and metabolism. The parasympathetic system acts to conserve energy and promote rest through decreased heart rate and increased digestion. The ANS regulates organ systems like the heart, lungs, and digestive system through both divisions to maintain homeostasis.
Baroreceptor Reflex Mechanism
Baroreceptors in the arteries detect changes in blood pressure and relay this information to the autonomic nervous system. The autonomic nervous system then works to maintain blood pressure within a normal range by increasing or decreasing total peripheral resistance and cardiac output through sympathetic or parasympathetic activation. Baroreceptors form a negative feedback loop, where increases in blood pressure lead to reductions in sympathetic activity and increases in parasympathetic activity to lower blood pressure back to normal levels.
Nervous system
The document discusses the structure and function of the nervous system. It notes that neurons, along with supporting glial cells, make up the central and peripheral nervous systems. Information is transmitted between neurons electrochemically through cell bodies, axons, and synapses using neurotransmitters. The central nervous system consists of the brain and spinal cord, which contain grey matter on the inside and white matter on the outside. The peripheral nervous system connects receptors, the CNS, and effectors through nerves. Sensory nerves transmit information from receptors to the CNS while motor nerves transmit information from the CNS to effectors.
Heart physiology
The document discusses cardiac muscle and the physiology of the heart. It describes the structure of cardiac muscle including specialized excitatory and conductive fibers. It explains the cardiac muscle action potential and how it differs from other muscles. The cardiac cycle and its components are outlined including atrial and ventricular systole and diastole. The roles of preload and afterload on heart function are introduced.
Cardiovascular physiology
This document provides an overview of cardiovascular physiology, including:
1) The anatomy of the heart and circulation of blood through the heart.
2) Electrical conduction system of the heart and the cardiac cycle.
3) Factors that can influence the cardiac cycle such as nerves, hormones, electrolytes.
4) Explanations of blood pressure, cardiac output, and factors influencing vascular function.
5) Some pathophysiologies that can occur in the cardiovascular system.
Neuromuscular junction
Neuromuscular transmission involves the synthesis and release of acetylcholine from motor neurons. Acetylcholine binds to nicotinic receptors on muscle fibers, causing depolarization and muscle contraction. Acetylcholine is quickly broken down by acetylcholinesterase to allow muscle relaxation. Drugs can mimic or block acetylcholine's effects at the neuromuscular junction to cause contraction or relaxation of muscle fibers.
Blood pressure mechanism
The document discusses the mechanisms that regulate blood pressure in the short term, including the nervous system and chemicals. It explains that the nervous system, including the baroreceptor reflex and chemoreceptors, controls blood pressure by changing peripheral resistance within seconds or minutes in response to changes in blood pressure. The document also outlines the roles of the vasomotor center, sympathetic and parasympathetic activity, and adrenal glands in short term blood pressure regulation.
Nervous system
The central nervous system (CNS) is made up of the brain and spinal cord. The brain controls most body functions, including awareness, movements, sensations, thoughts, speech and memory. The spinal cord is connected to the brain at the brain stem and is covered by the vertebrae of the spine.
Peripheral nerve system
The peripheral nervous system connects the central nervous system to the limbs and organs. It consists of the somatic nervous system, which controls voluntary movement, and the autonomic nervous system, which regulates involuntary functions. The autonomic nervous system has two divisions - the sympathetic nervous system, which activates the fight or flight response, and the parasympathetic nervous system, which promotes rest and digestion. Together these systems allow the nervous system to control and coordinate the body's activities.
Autonomic nervous system Physiology
The autonomic nervous system (ANS) controls involuntary functions like heartbeat, breathing, and digestion. It has two divisions - the sympathetic and parasympathetic systems.
The sympathetic system prepares the body for "fight or flight" through actions like increasing heart rate. It uses norepinephrine as a neurotransmitter. The parasympathetic system allows the body to "rest and digest" through actions like slowing the heart rate. It uses acetylcholine as a neurotransmitter.
Both systems involve two neurons - a preganglionic neuron from the CNS and a postganglionic neuron. They differ in the lengths of their neurons and the locations of their cell bodies. Together they work to maintain homeostasis through complementary
Cardiac cycle
The document provides an overview of the cardiovascular system, including the structure and function of the heart, properties of cardiac muscle, the cardiac cycle, heart sounds and murmurs, electrocardiography, congenital and acquired heart diseases, and considerations for dental care for patients with heart conditions. Key points covered include the layers of the heart wall, pacemaker cells, conduction system, electrical activity of cardiac muscle, stages of the cardiac cycle, classification of heart murmurs, common congenital defects like ventricular septal defect and tetralogy of Fallot, acquired conditions like rheumatic fever and infective endocarditis, and prophylactic measures for dental procedures in high-risk patients.
Coronary circulation
The coronary circulation consists of the arterial supply, venous drainage and lymphatic drainage of the heart. The heart receives its blood supply from the right and left coronary arteries. The right coronary artery supplies the right atrium and ventricle while the left coronary artery supplies the left atrium and ventricle. Coronary blood flow is regulated by physical, chemical, neural and hormonal factors to meet the metabolic demands of the heart. Coronary artery disease can lead to conditions like angina pectoris and myocardial infarction due to reduced blood supply to the heart muscle.
Phonocardiography(PCG)
Graphic record heart sound - Phonogram.
Recording the sounds connected with the pumping action of heart.
Sound from heart – phonocardiogram
Instrument to measure this – phonocardiograph
Basic function – to pick up the different heart sound,filter the required and display.
Heart*
The document summarizes regulation of heart pumping and control of the heart rate. It discusses the Frank-Starling law where the volume of blood ejected depends on the volume present in the ventricle at the end of diastole. It also describes control of the heart by the autonomic nervous system, with the sympathetic nervous system increasing heart rate and contractility and the parasympathetic nervous system decreasing heart rate. The normal electrocardiogram waveform is also summarized.
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Heart rate
Heart rate is the number of heartbeats per unit of time, usually per minute.
The heart rate is based on the number of contractions of the ventricles (the lower chambers of the heart).
Physiology of heart
The document summarizes the conduction system of the heart and the cardiac cycle. It discusses the following key points:
1. The heart's conduction system originates in specialized cardiac muscle cells called autorhythmic cells, which generate electrical impulses to initiate and coordinate heart contractions. The main structures of the conduction system are the sinoatrial node, atrioventricular node, bundle of His, and Purkinje fibers.
2. The cardiac cycle involves coordinated contraction and relaxation of the atria and ventricles. It begins with depolarization of the sinoatrial node, followed by atrial contraction, ventricular depolarization through the conduction system, ventricular contraction, and finally relaxation of both chambers.
Reticular formation in control of motor functions
The reticular formation is located in the central core of the brainstem and controls motor functions through direct and indirect projections. It contains two reticulospinal tracts - the medial and lateral tracts - that project to different regions of the spinal cord and modulate muscle tone, reflexes, posture, and movement. The reticular formation also projects to motor control centers in the brainstem, cerebellum, basal ganglia, and cortex to regulate skeletal muscle activity during facial expressions, voluntary movement, respiration, and maintaining balance and posture.
cardiac cycle
This document discusses cardiovascular physiology, beginning with an overview of the cardiac cycle and events in the cycle. It then covers determinants of myocardial performance including preload, afterload, contractility, and heart rate. Pressure-volume loops are introduced as a way to assess ventricular function. Physiological and pathological hypertrophy are compared. Key aspects covered include the Wiggers diagram, Frank-Starling mechanism, Anrep effect, Bowditch phenomenon, and formulas for calculating cardiac values.
Cardiac cycle physiology_4_dpt
The cardiac cycle describes the repeating sequence of events in the heart during one heartbeat. It begins with atrial systole which fills the ventricles with blood. This is followed by ventricular systole where the ventricles contract and eject blood out of the heart. The cardiac cycle is regulated by the heart's conduction system which coordinates the contractions of the atria and ventricles. It ensures the atria contract before the ventricles so blood is pumped efficiently through the heart and circulatory system with each heartbeat.
Blood pressure mechanism
Short-term regulation of blood pressure involves nervous and chemical mechanisms that act within seconds or minutes to control blood pressure. The nervous system regulates blood pressure by changing blood vessel diameter and heart rate through the sympathetic and parasympathetic nervous systems. Baroreceptors in the carotid sinus and aortic arch detect changes in blood pressure and stimulate reflex responses to return blood pressure to normal levels. Chemoreceptors sense oxygen and carbon dioxide levels and stimulate responses to maintain proper gas exchange in the lungs and tissues. If blood pressure drops severely, the brain triggers a central nervous system ischemic response to rapidly constrict blood vessels and raise blood pressure.
cardiac physiology
The document summarizes key aspects of cardiac physiology, including:
- The functions of the heart in generating blood pressure, routing blood flow, ensuring one-way flow, and regulating blood supply.
- The cardiac cycle and its phases of isovolumic contraction, ejection, isovolumic relaxation, and diastole.
- Factors that affect cardiac output including venous return, heart rate, contractility, and peripheral resistance.
- Key reflexes that regulate cardiac function such as the baroreceptor, chemoreceptor, and Bezold-Jarisch reflexes.
The Cardiovascular System
The document summarizes the anatomy and physiology of the cardiovascular system. It describes the location and structure of the heart, including its layers, chambers, and valves. It then discusses the cardiac conduction system, including the sinoatrial node which acts as the pacemaker, and how electrical signals cause coordinated heart contractions and relaxation. It concludes by defining cardiac output and some of the key factors that can influence it, such as heart rate, stroke volume, sympathetic tone, preload and afterload.
Autonomic nervous system
The autonomic nervous system (ANS) controls involuntary bodily functions and is divided into the sympathetic and parasympathetic nervous systems. The sympathetic system prepares the body for "fight or flight" through increased heart rate, breathing, and metabolism. The parasympathetic system acts to conserve energy and promote rest through decreased heart rate and increased digestion. The ANS regulates organ systems like the heart, lungs, and digestive system through both divisions to maintain homeostasis.
Baroreceptor Reflex Mechanism
Baroreceptors in the arteries detect changes in blood pressure and relay this information to the autonomic nervous system. The autonomic nervous system then works to maintain blood pressure within a normal range by increasing or decreasing total peripheral resistance and cardiac output through sympathetic or parasympathetic activation. Baroreceptors form a negative feedback loop, where increases in blood pressure lead to reductions in sympathetic activity and increases in parasympathetic activity to lower blood pressure back to normal levels.
Nervous system
The document discusses the structure and function of the nervous system. It notes that neurons, along with supporting glial cells, make up the central and peripheral nervous systems. Information is transmitted between neurons electrochemically through cell bodies, axons, and synapses using neurotransmitters. The central nervous system consists of the brain and spinal cord, which contain grey matter on the inside and white matter on the outside. The peripheral nervous system connects receptors, the CNS, and effectors through nerves. Sensory nerves transmit information from receptors to the CNS while motor nerves transmit information from the CNS to effectors.
Heart physiology
The document discusses cardiac muscle and the physiology of the heart. It describes the structure of cardiac muscle including specialized excitatory and conductive fibers. It explains the cardiac muscle action potential and how it differs from other muscles. The cardiac cycle and its components are outlined including atrial and ventricular systole and diastole. The roles of preload and afterload on heart function are introduced.
Cardiovascular physiology
This document provides an overview of cardiovascular physiology, including:
1) The anatomy of the heart and circulation of blood through the heart.
2) Electrical conduction system of the heart and the cardiac cycle.
3) Factors that can influence the cardiac cycle such as nerves, hormones, electrolytes.
4) Explanations of blood pressure, cardiac output, and factors influencing vascular function.
5) Some pathophysiologies that can occur in the cardiovascular system.
Neuromuscular junction
Neuromuscular transmission involves the synthesis and release of acetylcholine from motor neurons. Acetylcholine binds to nicotinic receptors on muscle fibers, causing depolarization and muscle contraction. Acetylcholine is quickly broken down by acetylcholinesterase to allow muscle relaxation. Drugs can mimic or block acetylcholine's effects at the neuromuscular junction to cause contraction or relaxation of muscle fibers.
Blood pressure mechanism
The document discusses the mechanisms that regulate blood pressure in the short term, including the nervous system and chemicals. It explains that the nervous system, including the baroreceptor reflex and chemoreceptors, controls blood pressure by changing peripheral resistance within seconds or minutes in response to changes in blood pressure. The document also outlines the roles of the vasomotor center, sympathetic and parasympathetic activity, and adrenal glands in short term blood pressure regulation.
Nervous system
The central nervous system (CNS) is made up of the brain and spinal cord. The brain controls most body functions, including awareness, movements, sensations, thoughts, speech and memory. The spinal cord is connected to the brain at the brain stem and is covered by the vertebrae of the spine.
Peripheral nerve system
The peripheral nervous system connects the central nervous system to the limbs and organs. It consists of the somatic nervous system, which controls voluntary movement, and the autonomic nervous system, which regulates involuntary functions. The autonomic nervous system has two divisions - the sympathetic nervous system, which activates the fight or flight response, and the parasympathetic nervous system, which promotes rest and digestion. Together these systems allow the nervous system to control and coordinate the body's activities.
Autonomic nervous system Physiology
The autonomic nervous system (ANS) controls involuntary functions like heartbeat, breathing, and digestion. It has two divisions - the sympathetic and parasympathetic systems.
The sympathetic system prepares the body for "fight or flight" through actions like increasing heart rate. It uses norepinephrine as a neurotransmitter. The parasympathetic system allows the body to "rest and digest" through actions like slowing the heart rate. It uses acetylcholine as a neurotransmitter.
Both systems involve two neurons - a preganglionic neuron from the CNS and a postganglionic neuron. They differ in the lengths of their neurons and the locations of their cell bodies. Together they work to maintain homeostasis through complementary
Cardiac cycle
The document provides an overview of the cardiovascular system, including the structure and function of the heart, properties of cardiac muscle, the cardiac cycle, heart sounds and murmurs, electrocardiography, congenital and acquired heart diseases, and considerations for dental care for patients with heart conditions. Key points covered include the layers of the heart wall, pacemaker cells, conduction system, electrical activity of cardiac muscle, stages of the cardiac cycle, classification of heart murmurs, common congenital defects like ventricular septal defect and tetralogy of Fallot, acquired conditions like rheumatic fever and infective endocarditis, and prophylactic measures for dental procedures in high-risk patients.
Coronary circulation
The coronary circulation consists of the arterial supply, venous drainage and lymphatic drainage of the heart. The heart receives its blood supply from the right and left coronary arteries. The right coronary artery supplies the right atrium and ventricle while the left coronary artery supplies the left atrium and ventricle. Coronary blood flow is regulated by physical, chemical, neural and hormonal factors to meet the metabolic demands of the heart. Coronary artery disease can lead to conditions like angina pectoris and myocardial infarction due to reduced blood supply to the heart muscle.
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Phonocardiography(PCG)
Graphic record heart sound - Phonogram.
Recording the sounds connected with the pumping action of heart.
Sound from heart – phonocardiogram
Instrument to measure this – phonocardiograph
Basic function – to pick up the different heart sound,filter the required and display.
Heart*
The document summarizes regulation of heart pumping and control of the heart rate. It discusses the Frank-Starling law where the volume of blood ejected depends on the volume present in the ventricle at the end of diastole. It also describes control of the heart by the autonomic nervous system, with the sympathetic nervous system increasing heart rate and contractility and the parasympathetic nervous system decreasing heart rate. The normal electrocardiogram waveform is also summarized.
Phonocardiogram
This document discusses phonocardiography, which is a technique that graphically records cardiac acoustic phenomena like heart sounds and murmurs. It describes how phonocardiography can help evaluate heart sounds with respect to electric and mechanical cardiac cycle events. Advanced digital techniques and signal processing algorithms now allow more accurate analysis of phonocardiograms compared to conventional methods. Both pediatric and adult heart sound analysis can benefit from phonocardiography to differentiate normal from abnormal findings.
Heart physiology
The document describes the conduction system of the heart, which coordinates contraction of the atria and ventricles. It is made up of the sinoatrial node, atrioventricular node, bundle of His, bundle branches, and Purkinje fibers. Together this system ensures the atria contract before the ventricles to efficiently pump blood throughout the body and heart. An electrocardiogram measures the electric currents produced during conduction to evaluate heart function.
Cardiac conduction system
The cardiac conduction system is made up of four main structures that stimulate contraction of the heart muscle in a coordinated way. The sinoatrial node acts as the pacemaker and initiates electrical impulses throughout the heart. The atrioventricular node receives impulses from the atria and slows conduction to allow for proper atrial contraction before ventricular contraction. Impulses then travel through the atrioventricular bundle and Purkinje fibers to coordinate simultaneous contraction of the ventricles. An electrocardiogram is used to measure the electrical activity of the heart and detect any abnormalities.
A heart physiology
1) The heart has four chambers and uses electrical signals to coordinate contractions that pump blood through two circuits.
2) The sinoatrial node initiates electrical impulses that spread through the heart, causing atria to contract before ventricles.
3) Cardiac output depends on heart rate, preload, afterload and contractility and is regulated by nervous and hormonal factors.
CV CONTROL DURING EXERCISE
During exercise, the cardiovascular system responds to increase delivery of oxygen and nutrients to working muscles. The heart rate increases to pump more blood with each contraction. The left ventricle increases in size to pump more blood per beat, increasing stroke volume and cardiac output. Blood is redirected away from organs and toward active muscles and skin. Arrhythmias are disruptions to the heart's normal rhythm that can be benign or life-threatening depending on severity. The electrocardiogram monitors the heart's electrical activity through the cardiac cycle.
the cardiovascular system and Physiology of heart
The document discusses the cardiovascular system and physiology of the heart. It describes the components of the cardiovascular system including the heart, blood vessels, and blood. It explains the basic functions of these parts, including that the heart acts as a pump to circulate blood through two circuits - the pulmonary and systemic circulations. It also provides details on the anatomy and functions of the heart chambers and valves, as well as blood flow, vessels, heart sounds, and blood characteristics.
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Heart
The document summarizes key aspects of heart physiology:
- The heart pumps blood through two circuits and uses valves to ensure one-way blood flow.
- Cardiac muscle cells contract as a unit due to intercalated disks and gap junctions.
- The heart's conduction system uses specialized pacemaker cells and Purkinje fibers to coordinate contractions.
- An electrocardiogram tracks the heart's electrical activity during a cardiac cycle of atrial and ventricular filling/contraction.
Heart actions 2
The document describes the cardiac cycle and how blood flows through the heart. It discusses:
1) The cardiac cycle is a coordinated series of events in the heart that ensures proper blood flow. It involves the alternating contraction and relaxation of the atria and ventricles.
2) Key steps include atrial systole filling the ventricles with blood followed by ventricular systole which pumps blood out of the heart.
3) The cardiac conduction system coordinates the heartbeat and includes the sinoatrial node which initiates impulses and the atrioventricular node which relays signals to the ventricles.
Cardio physio
The heart functions to pump blood throughout the body via two circulatory systems - pulmonary and systemic. It generates blood pressure and ensures one-way blood flow. Cardiac output, the amount of blood pumped, is determined by heart rate and stroke volume. Intrinsic factors like the Frank-Starling mechanism and extrinsic neural and hormonal controls regulate cardiac output in response to the body's changing needs.
3.heart
The document discusses the structure and function of the heart. It describes how the heart is composed of contractile cardiac muscle cells that pump blood, as well as a conducting system of specialized cells that coordinate the heartbeat. The conducting system includes nodal cells that set the heart rate and conducting cells that distribute electrical signals to make the heart chambers contract in the proper sequence. The document explains how factors like blood volume, autonomic innervation, and hormones regulate cardiac output by influencing heart rate and stroke volume.
Cv System1
The cardiovascular system consists of the heart and blood vessels. The heart pumps blood through two circuits - pulmonary circulation to the lungs and systemic circulation to the rest of the body. The cardiac cycle occurs every 0.8 seconds through systole (contraction) and diastole (relaxation). The heart's conduction system uses electrical signals from the sinoatrial node to coordinate contractions of the atria and ventricles. Electrocardiograms track this electrical activity through waves. The heart rate is controlled both neurally through the autonomic nervous system and hormonally.
The Heart
The document discusses the cardiac cycle, cardiac blood flow, and the intrinsic conduction system of the heart. It explains that the sinoatrial node initiates impulses that travel through the atrioventricular node and bundle of His to stimulate ventricular contraction. It also reviews factors that influence stroke volume and cardiac output, such as preload, contractility, and the autonomic nervous system.
Circulatory system - The Heart
Describe the structure of the heart
Explain the importance of the valves
Describe the cardiac cycle
List the factors that leads to the heartbeat
cardiovascular disruptions
Cardiovascular disruptions can be caused by a lack of blood supply to the heart, infections of the heart, or immune-mediated inflammatory conditions. A lack of blood supply can result in ischemia, angina, heart attacks, and heart failure. Infections can directly damage the heart valves and decrease cardiac output. Common infections include infective endocarditis from bacteria entering the bloodstream, and rheumatic heart disease from an untreated streptococcal infection which causes inflammation of the heart valves.
Ap heart chp18part2
This document discusses the anatomy and physiology of the heart. It covers topics like cardiac muscle contraction, the sequence of heart excitation starting from the sinoatrial node, the relationship between heart electrical activity and the electrocardiogram, heart sounds, phases of the cardiac cycle, and regulation of heart rate by the autonomic nervous system. It also briefly discusses congenital heart defects, developmental aspects of the heart, and age-related changes affecting the heart.
Cardiovascular system I.pptx
This document provides an overview of the cardiovascular system. It discusses the key structures and functions of the heart including the four chambers, valves, pacemaker tissue, and cardiac cycle. It also covers circulation, properties of cardiac muscle, factors affecting cardiac output, and the electrocardiogram. Regulation of the cardiovascular system is achieved through local autoregulatory mechanisms and systemic regulatory mechanisms, including chemical and neural factors.
Cvs7
The document summarizes the cardiovascular system and regulation of blood pressure. It describes how the brain monitors and controls blood flow and pressure on a beat-to-beat basis to meet metabolic demands. Blood pressure is influenced by cardiac output, peripheral resistance, and blood volume. The document then discusses short term regulation of blood pressure by baroreceptor reflexes, chemoreceptor reflexes, and local mechanisms, as well as long term regulation by the renal-body fluid system including the renin-angiotensin-aldosterone mechanism.
Johny's A&P ECG, cardiac cycle and cardiac output
The document discusses electrocardiography (ECG), which involves using electrodes to detect and record the electrical activity of the heart over time. It provides a brief history of ECG development and describes the modern ECG machine. It then explains the electrical conduction system of the heart and the waves that make up a normal ECG, including the P, QRS, and T waves. The cardiac cycle and heart sounds are also summarized.
Cardiovascularsystem 110221045748-phpapp02
The cardiovascular system consists of the heart and blood vessels. The heart has four chambers and uses valves to ensure one-way blood flow. It pumps deoxygenated blood to the lungs and oxygenated blood throughout the body. Blood travels through arteries, capillaries, and veins in both pulmonary and systemic circuits. The heart's conduction system uses electrical signals to coordinate contractions. Factors like preload and afterload influence cardiac output. Blood pressure is regulated by baroreceptors, chemoreceptors, and the renin-angiotensin system.
Nervous and hormonal regulation of heart beat.pptx
nervous and hormonal regulation of heartbeat
Heart rate refers to the number of times the heart beats per minute and is directly related to workload being placed on the heart
The normal heart rate of resting adult human- 60-100
Bradycardia- slow heart rate (below 60 bpm)
Tachycardia- fast heart rate (above 100 bpm)
Irregular pattern in heart beating is termed as Arrhythmia
Heart excitation
The document summarizes key aspects of heart physiology:
1. The heart generates blood pressure, routes blood flow through two circuits (pulmonary and systemic), and ensures one-way blood flow through valves.
2. The left side of the heart is more muscular to pump blood throughout the body. Valves prevent backflow of blood.
3. Cardiac muscle contracts as a unit through a conduction system including the sinoatrial node, atrioventricular node, and Purkinje fibers.
4. An electrocardiogram records the heart's electrical activity and can indicate damage or abnormalities.
CONTROL OF ARTERIAL BLOOD PRESSURE.pptx
The document discusses the circulatory system and blood pressure regulation. It describes the different types of blood vessels - arteries, arterioles, capillaries and veins. Arteries carry blood away from the heart while veins carry blood back to the heart. Capillaries are where gas and nutrient exchange occurs. Blood pressure is regulated through short-term mechanisms like the baroreceptor reflex and long-term mechanisms like the renin-angiotensin system. Heart failure and shock can occur if the heart or blood vessels are unable to effectively circulate blood and maintain adequate blood pressure.
Circulatory responses to exercise
The document discusses the circulatory system's response to exercise. The primary purpose is to deliver adequate oxygen and remove waste from tissues. During heavy exercise, oxygen demand can increase 15-25 times resting levels. To meet this, cardiac output and blood flow to active muscles increase through two mechanisms: 1) increased heart rate and stroke volume leading to higher cardiac output, and 2) redistribution of blood flow from inactive organs to working muscles. Proper circulatory function is critical for exercise and maintaining homeostasis.
cardiac cycle.pptx ESSENTIAL INFORMATIONS TO STUDY
The cardiac cycle describes the series of events that occur with each heartbeat. It involves both atrial and ventricular systole (contraction) and diastole (relaxation). The cycle is typically divided into systole and diastole. Key phases include atrial systole, isovolumic contraction, ejection, isovolumic relaxation, and filling. The total duration is approximately 0.8 seconds in adults. Cardiac output refers to the volume of blood pumped by each ventricle per minute and is regulated by factors like heart rate, stroke volume, contractility, and peripheral resistance.
Similar to The Heart (20)
Nervous and hormonal regulation of heart beat.pptx
Nervous and hormonal regulation of heart beat.pptx
cardiac cycle.pptx ESSENTIAL INFORMATIONS TO STUDY
cardiac cycle.pptx ESSENTIAL INFORMATIONS TO STUDY
The Heart
- 1. The Heart
- 7. Cardiac vs. Skeletal Muscle Contraction Tetanus occurs because short refractory period Long refractory period which continues while relaxing = no tetanus! Type of contraction Initiate contraction Delay repolarization & initiate contraction Extracellular Calcium Ions Duration: 10 msec Duration: 250-300 msec Action Potential Skeletal Muscle Cardiac Muscle