A/P - Heart (Ch 12)
The combined effect of a) & b) is to LOWER BLOOD PRESSURE (decrease).
ANP (atrial natriuretic peptide) also stimulates the conversion of white adipocytes to brown adipocytes so that fats are not stored, but rather their energy is released in the form of HEAT.
During one cardiac cycle: The atria contract first, followed by contraction of the ventricles.
Backflow of blood from the ventricles to the atria is prevented by the: mitral and tricuspid valves
The outermost of the pericardial membranes is the: fibrous pericardium
Each normal heartbeat is initiated by the: SA node
Problem: During exercise, pulse is 120 bpm and stroke volume is 100 mL. What is the cardiac output? 12 L (100 x 120)
If resting cardiac output is 6 L, and maximum exercise cardiac output is 16 L, what is the cardiac reserve? 10 L (16 - 6)
A heart rate below bpm is called: bradycardia
The coronary sinus receives blood directly from the: coronary veins
Sympathetic nerves to the heart transmit impulses that INCREASE heart rate and force of contraction.
The parasympathetic nerves to the heart are the VAGUS NERVES, which transmit impulses that DECREASE heart rate.
The function of the serous fluid of the pericardial membranes is to: prevent friction as the heart beats
The purpose of the coronary vessels is to: circulate blood through the heart
To bring about changes in heart rate, the medulla must receive sensory information. The receptors that detect changes in blood pressure are called PRESSORECEPTORS and they are located in the CAROTID sinus and the AORTIC sinus.
The receptors that detect changes in the oxygen level of the blood are called CHEMORECPTORS, and they are located in the CAROTID body and the AORTIC body.
The first heart sound is caused by the closure of the A.V. valves
The second heart sound is cause by the closure of the _____ valves
The sensory nerves for the carotid sinus and body are the GLOSSOPHARYNGEAL nerves.
The sensory nerves for the aortic sinus and body are the VAGUS nerves.
Natural pacemaker of the heart: SA NODE (sinoatrial node or sinus node)
Upper chamber of the heart: ATRIUM
The sequence of events in one heartbeat is called the:
cardiac cycle
A blood pressure reading:
has the systolic value first
Cardiac output is the amount of blood pumped by the ventricle in:
one minute
An anastomosis in the vascular system is a connection between:
two arteries or two veins
Which pair of chambers has the thicker wall? -->
ventricles
Which statement is NOT true of cardiac output? 1) Cardiac output is the amount of blood pumped by a ventricle in one beat. 2) A normal cardiac output is necessary to maintain normal blood pressure. 3) Cardiac output equals stroke volume times pulse rate. 4) A normal cardiac output is necessary to maintain oxygenation of tissues.
# 1 Correct the statement: Cardiac output is the amount of blood pumped by a ventricle in one minute.
Which statement is NOT true of the valves of the heart? 1) The mitral valve prevents backflow of blood from the right ventricle to the right atrium. 2) The right and left AV valves are anchored by papillary muscles and chordae tendineae. 3) The semilunar valves prevent backflow of blood from the arteries to the ventricles. 4) The valves are made of endocardium reinforced with connective tissue.
# 1 Correct the statement: The mitral valve prevents backflow of blood from the right ventricle to the LEFT atrium.
Which statement is NOT true of coronary circulation? 1) The two major coronary arteries are branches of the aorta. 2) The coronary sinus empties blood from the myocardium into the left atrium. 3) For the myocardium, the most important substance in the blood is oxygen. 4) Myocardium that is deprived of oxygen becomes ischemic.
# 2 Correct the statement: The coronary sinus empties blood from the myocardium into the RIGHT atrium.
Which statement is NOT true of the heart's response to exercise? 1) Starling's law permits the heart to contract more forcefully in response to increased venous return. 2) The heart rate will increase in response to parasympathetic impulses. 3) Stroke volume increases during exercise as the heart pumps more forcefully. 4) Cardiac output increases to supply more oxygen to the body.
# 2 Correct the statement: The heart rate will increase in response to SYMPATHETIC impulses.
Which statement is NOT true of the chambers and vessels of the heart? 1) Both ventricles pump blood into arteries. 2) The left ventricle pumps blood into the pulmonary artery. 3) The left atrium receives blood from the pulmonary veins. 4) The right atrium receives blood from the superior and inferior caval veins.
# 2 Correct the statement: The left ventricle pumps blood into the AORTA.
Which statement is NOT true of the regulation of heart rate? 1) The cardiac centers are located in the medulla. 2) Sympathetic impulses to the heart decrease the heart rate. 3) Pressoreceptors detect changes in blood pressure to supply sensory information to the medulla. 4) The parasympathetic nerves to the heart are the vagus nerves.
# 3 Correct the statement: Sympathetic impulses to the heart INCREASE the heart rate. *OR* PARASYMPATHETIC impulses to the heart DECREASE the heart rate.
Which statement is NOT true of the cardiac conduction pathway? 1) The Purkinje fibers carry impulses to the ventricular myocardium. 2) The bundle of His is located in the upper interventricular septum. 3) The AV node initiates each heartbeat. 4) The SA node and AV node promote contraction of the atria.
# 3 Correct the statement: The SA NODE initiates each heartbeat.
Which statement is NOT true of heart rate? 1) The normal range of heart rate for a healthy adult is 60-80 beats per minute. 2) An infant may have a normal rate as high as 120 beats per minute. 3) An athlete's heart rate may range from 40 to 60 beats per minute. 4) An athlete's heart rate is low because the heart's stroke volume is lower.
# 4 Correct the statement: An athlete's heart rate is low because the heart's stroke volume is HIGHER.
Which statement is NOT true of the pericardia membranes? 1) Serous fluid prevents friction between the serous layers as the heart beats. 2) The fibrous pericardium is the thick, outermost layer. 3) The parietal pericardium lines the fibrous pericardium. 4) The visceral pericardium may also be called endocardium.
# 4 Correct the statement: The visceral pericardium may also be called the EPICARDIUM.
Which statement is NOT true of the cardiac cycle? 1) Most blood flow from the atria to the ventricles flows passively. 2) All blood flow from ventricles to arteries is actively pumped. 3) The atria contract first, then the ventricles contract. 4) When the atria are in systole, the ventricles are in systole.
# 4 Correct the statement: When the atria are in systole, the ventricles are in DIASTOLE.
Number the events of one cardiac cycle in the proper sequence. -->
1 - Blood continuously flows into both atria 2 - The pressure of incoming blood opens the right and left AV valves 3 - 2/3 of the atrial blood flows passively into the ventricles 4 - The atria contract to pump the remaining blood into the ventricles 5 - The atria relax, and the ventricles begin to contract 6 - The right and left AV valves are closed, and the aortic and pulmonary semilunar valves are opened 7 - Ventricular contraction pumps blood into the arteries 8 - The ventricles relax, and the semilunar valves are closed
Name the parts of the conduction pathway in order. -->
1 - SA node - in the all of the right atrium 2 - AV node - in the lower interatrial septum 3 - Bundle of His - in the upper interventricular septum 4 - Bundle of branches - extend through the interventricular septum 5 - Purkinje fibers - to the rest of the myocardium of the ventricles
Number the following in proper sequence with respect to the flow of blood through the heart to and from the body and lungs -->
1 - left atrium 2 - left ventricle 3 - aorta 4 - body 5 - superior and inferior caval veins 6 - right atrium 7 - right ventricle 8 - pulmonary artery 9 - lungs 10 - pulmonary veins
When blood pressure to the brain decreases, a reflex arc serves to restore the blood pressure to normal. Put the steps of the arc in order, beginning with the stimulus. =>
1- blood pressure to the brain decreases 2- detection by pressoreceptors in the carotid sinuses 3- fewer sensory impulses are sent to the medulla along Cranial Nerves IX 4- accelerator center is stimulated to generate impulses 5- motor impulses travel along sympathetic nerves SA node, AV node, and ventricular myocardium 6- heart rate and force of contraction increases 7- blood pressureto the brain is raised to normal 8- inhibitory center sends parasympathetic impulses along vagus nerves 9- parasympathetic impulses reach the SA and AV nodes of the heart 10- heart rate slows to normal resting pace
Trace the pathway of blood flow of one red blood cell -- from the point where oxygenated blood is received by the heart to the myocardium to the point immediately prior to deoxygenated blood leaving the heart =>
1- left atrium 2- left ventricle 3- ascending aorta 4- right and left coronary arteries 5- smaller arteries 6- myocardial capillaries 7- coronary veins 8- coronary sinus 9- right atrium 10- right ventricle
How many layers of pericardial membranes are around the heart? -->
3
Put the parts of the aorta in the proper sequence, beginning at the left ventricle: 1. abdominal aorta 2. aortic arch 3. ascending aorta 4. thoracic aorta
3, 2, 4, 1
A basketball player has a resting cardiac output of 5500 mL, and a stroke volume of 100 mL. What is the pulse?
55 bpm
Name the parts of the conduction pathway that bring about atrial systole. SA NODE & AV NODE
??? Name the parts of the conduction pathway that bring about ventricular systole. Bundle of His, branches, and Purkinje fibers
PULMONARY SEMILUNAR VALVE Location: At the junction of the right ventricle and the pulmonary artery Function: Prevents backflow of blood to the right ventricle when the ventricle relaxes
AORTIC SEMILUNAR VALVE Location: At the junction of the left ventricle and the aorta Function: Prevents backflow of blood to the left ventricle when the ventricle relaxes
In the cardiac cycle, which statement is true of blood flow from the ventricles to the arteries?
All blood is actively pumped.
Visceral pericardium: EPICARDIUM
Amount of blood pumped by a ventricle in 1 minute: CARDIAC OUTPUT
Irregular heartbeats: ARRYTHMIAS
Amount of blood pumped by a ventricle per beat: STOKE VOLUME
Electrically, an action potential is DEPOLARIZATION followed by REPOLARIZATION.
An action potential involves the entry of SODIUM IONS into the muscle fiber, followed by the exit of POTASSIUM IONS from the muscle fibers.
Cardiac muscle cells are branched and may also be called MUSCLE FIBERS (MYOCYTES).
Cardiac muscle cells have many mitochondria, the function of which is to produce ATP.
Athletes in good physical condition often have LOWER heart rates than do other adults.
Cardiac output is the amount of blood pumped by a ventricle in 1 minute.
Name the vital sign that is a measure of heart rate. PULSE
Children and infants usually have HIGHER heart rate than do adults, because children are smaller.
Name the organ directly below the heart. -->
DIAPHRAGM
Contraction of chambers of the heart: SYSTOLE
First branches of the ascending aorta: CORONARY ARTERIES
From atria to ventricles, most blood FLOWS PASSIVELY.
From ventricles to arteries, all blood IS PUMPED.
The MITRAL VALVE prevents backflow of blood from the left ventricle to the left atrium.
Largest artery of the body: AORTA
Mr. D is 43 years old, and his father died of a heart attack at the age of 40. Mr. D's favorite meal is steak and a backed potato with butter. He also smokes a pack of cigarettes each day and says he doesn't get much chance to exercise. Mr. D is a person at high risk for a MYOCARDIAL INFARCTION (heart attack).
List 4 risk factors that Mr. D has: 1. heredity (family history) 2. high fat diet 3. smoking 4. little exercise
TRICUSPID VALVE Location: Between the right atrium and right ventricle Function: Prevents backflow of blood to the right atrium when the right ventricle contracts
MITRAL VALVE Location: Between the left atrium and left ventricle Function: Prevents backflow of blood to the left atrium when the left ventricle contracts
The cardiac conduction pathway is the pathway of electrical impulses throughout the heart during each heartbeat.
Must the heart receive nerve impulses to cause contraction? NO
Mr. W is 55 years old and has been hospitalized for surgery to implant an artificial pacemaker for his heart. The heart's own natural pacemaker, which is not functioning properly, is the SA node. Without an artificial pacemaker to maintain a normal heart rate, the remainder of Mr. W's heart would continue to beat but at a SLOWER rate. What would happen to Mr. W's cardiac output? DECREASE
Name the cardiac disorder suggested by each statement: 1. An abnormal extra sound heard during the cardiac cycle: HEART MURMOR 2. Death of heart muscle due to lack of oxygen: MYOCARDIAL INFARCTION 3. Lipid deposits within the coronary arteries: CORONARY ATHEROSCLEROSIS
The heart has 4 chambers; two upper chambers called ATRIA and two lower chambers called VENTRICLES.
Name the tissue that forms the walls of these chambers; CARDIAC MUSCLE, or its other name, MYOCARDIUM.
The cardiac centers are located in the MEDULLA of the brain.
Name the two centers: the accelerator and the inhibiting centers
TRICUSPID valve; prevents backflow of blood from the right ventricle to the right atrium
Narrowing of a valve: STENOSIS
Cardiac muscle tissue: MYOCARDIUM
Part of the myocardium is deprived of its blood supply and becomes: ISCHEMIC
Problem: Pulse is 60 bpm and stroke volume is 75 mL. What is the cardiac output? 4.5 L (75 x 60)
Problem: An athlete's resting cardiac output is 6000 mL per minutes, and her stroke volume is 100 mL per beat. What is her pulse? 60 bpm
LEFT ATRIUM: Vessel: Pulmonary veins Function of Vessel: Return blood from the lungs
RIGHT ATRIUM Vessel: Superior and inferior caval veins Function of Vessel: Return blood from the body
LEFT VENTRICLE: Vessel: Aorta Function of Vessel: Takes blood to the body
RIGHT VENTRICLE Vessel: Pulmonary artery Function of Vessel: Takes blood to the lungs
Area in the thoracic cavity between the lungs: MEDIASTINUM
Relaxation of chambers of the heart: DIASTOLE
The cardiac cycle is the term for the sequence of events in one HEART BEAT.
SYSTOLE means CONTRACTION DIASTOLE means RELAXATION
The amount of blood that returns to the heart: VENOUS RETURN
Sequence of events in one heartbeat: CARDIAC CYCLE
When venous return increases, the heart contracts more forcefully. This is called:
Starling's law of the heart, and it increases cardiac output
The most serious arrhythmia is FIBRILLATION, which is very rapid and uncoordinated.
State a normal range of resting heart rate for a healthy adult. 60-80 bpm
What will happen to a part of the heart muscle that is deprived of its blood supply? The heart muscle cells begin to die.
State one possible cause for the previous question. A blood clot (or atherosclerosis) in a coronary vessel.
State a normal range of resting stroke volume. 60-80 mL per beat
State the formula used to determine cardiac output: CARDIAC OUTPUT = STROKE VOLUME x PULSE
Cardiac output is important to maintain normal BLOOD PRESSURE and to provide for the transport of OXYGEN to TISSUES.
Stroke volume is the amount of blood pumped by a ventricle in 1 beat.
Which of the following statements are true of the ANATOMY OF THE HEART: a) The chordae tendineae and the papillary muscles anchor the free edges of the AV valves. b) The function of the fibrous skeleton of the heart is to keep the thin-walled atria open at all times. c) The epicardium lines the heart and prevents blood clotting within the chambers. d) The right atrium receives blood from the lower and upper body. e) Blood to the body is pumped by the left ventricle into the aorta. f) The six pulmonary veins empty into the left atrium. g) The coronary vessels circulate blood throughout the myocardium. h) The lungs are lateral to the heart, and the diaphragm is inferior. i) The fibrous pericardium is the innermost of the pericardial membranes. j) The bundle of His is located in the upper interatrial septum. k) Intercalated discs permit the cusps of the AV valves to work smoothly. l) The tricuspid valve is between the left atrium and left ventricle.
TRUE a, d, e, g, h FALSE b, c, f, i, j, k, l
Which of the following statements are true of the PHYSIOLOGY OF THE HEART: a) Cardiac output equals stroke volume divided by pulse. b) The heart is a double pump, and both pumps work simultaneously. c) The action potential through the myocardium stimulates the mechanical contraction of the chambers of the heart. d) Only half of the blood that flows from the ventricles to the arteries is pumped. e) All of the blood that flows from the atria to the ventricles must be pumped. f) ANP is secreted by the atria in response to a higher blood volume or pressure. g) Impulses along the vagus nerves slow the heart rate. h) Ventricular systole closes the arterial semilunar valves. i) The cardiac centers of the CNS are located in the hypothalamus. j) The AV node has the fastest natural rate of depolarization. k) Epinephrine is the hormone that reinforces the effects of the parasympathetic nervous system. l) A person's average resting cardiac output is approximately equal to her or his total blood volume.
TRUE: b, c, f, g, l FALSE: a, d, e, h, i, j, k
Sensory impulses travel along the GLOSSOPHARYNGEAL nerves to the medulla of the brain.
The ACCELERATOR center is stimulated and generates impulses that are carried by SYMPATHETIC nerves to the heart.
The heart is actually a double pump, and both pumps work simultaneously. The LEFT SIDE of the heart receives blood from the lungs and pumps this blood to the body.
The RIGHT SIDE of the heart receives blood from the body and pumps this blood to the lungs.
The papillary muscles are columns of MYOCARDIUM that project into each VENTRICLE (chamber) of the heart.
The chordae tendineae are strands of FIBROUS CONNECTIVE tissue that extend from the papillary muscles to the flaps of the AV valves.
The right and left coronary arteries are branches of the AORTA.
The coronary sinus is formed by the union of coronary veins, and it returns blood from the myocardium to the RIGHT ATRIUM (chamber).
The first part of the cardiac conduction pathway in the ventricles is the: Bundle of His
The difference between resting cardiac output and maximum exercise cardiac output is called: cardiac reserve
Cardiac muscle cells generate their own action potentials, which means that they do not require NERVE IMPULSES in order to contract.
The electrical impulses of cardiac mycoytes spread quickly to adjacent cells because of the presence of INTERCALATED DISCS at the ends of the cells.
The chambers of the heart that receive blood from veins are the: right and left atria
The endocardium lines the chambers of the heart and: is smooth to prevent abnormal clotting within the heart
The cardiac cycle normally creates TWO heart sounds.
The extra sound heard during the cardiac cycle is called a HEART MURMOR.
The serous membrane that is on the surface of the heart muscle is called the VISCERAL pericardium, or the EPICARDIUM.
The function of the serous fluid produced by the serous layers is to PREVENT FRICTION as the heart beats.
The function of the heart is to PUMP BLOOD.
The heart is located in mediastinum, which is the area between the LUNGS in the THORACIC cavity.
The veins that return blood the right atrium are the: superior and inferior caval veins
The heart is located: medial to the lungs and superior to the diaphragm
Changes in blood pressure are detected by: pressoreceptors in the carotid and aortic sinuses
The hormone ANP increases the loss of _____ in urine to decrease blood volume and blood pressure. sodium ions & water
The effect of these impulses is to INCREASE heart rate and force of contraction to RAISE blood pressure back to normal.
The hormone that increases heart rate and force of contraction in stressful situations is EPINEPHRINE secreted by the ADRENAL MEDULLA.
Which statement is not true of the atria of the heart?
The left atrium receives blood from the upper body.
Which statement is not true of the ventricles of the heart?
The left ventricle has thin walls because the blood it pumps is only going to the body.
The chambers of the heart are lined with simple squamous epithelium called the ENDOCARDIUM, which also covers the VALVES of the heart.
The most important physical characteristic of the endocardium is that it's very SMOOTH, which prevents abnormal CLOTTING in the chambers of the heart.
The purpose of the coronary vessels is to circulate blood throughout the MYOCARDIUM (HEART).
The most important substance in the blood is OXYGEN.
The centers that regulate heart rate are located in the: medulla
The nerves that transmit impulses to decrease the heart rate are the: vagus nerves
The electrical cavity of the heart may be depicted in an: ECG
The normal heart sounds are caused by: closure of the valves
The outermost layer is called the FIBROUS pericardium and is made of FIBROUS CONNECTIVE TISSUE.
The serous membrane that lines the fibrous pericardium is called the PARIETAL pericardium.
The units of contraction of cardiac muscle fibers are SACROMERES.
The striations of cardiac fibers are the result of the arrangement of the contracting proteins MYOSIN and ACTIN.
The electrical activity of the heart can be recorded and depicted in and ECG.
The term for irregular heartbeats is ARRHYTHMIA.
Backflow of blood from the arteries to the ventricles is prevented by the: aortic and pulmonary semilunar valves
The vessel into which the left ventricle pumps blood is the: aorta
The wall of myocardium between the two atria is the INTERNAL SEPTUM.
The wall of myocardium between the two ventricles is the INTERVENTRICULAR SEPTUM.
The SA node initiates each heartbeat because it has the most RAPID rate of contraction.
This is so because the cells of the SA node are more permeable to SODIUM ions and DEPOLARIZE more rapidly than other cardiac muscle cells.
Mr. N has been hospitalized following a mild heart attack. His ECG is being monitored to detect possible ventricular fibrillation, which means: RAPID, UNCOORDINATED CONTRACTIONS
Ventricular fibrillation is a medical emergency because if the ventricles are fibrillating, they are not PUMPING BLOOD and cardiac output will DECREASE.
Heart chambers are lined with ENDOCARDIUM.
Very rapid and uncoordinated ventricular beat: FIBRILLATION
The regulation of heart rate is a reflex, that is, an automatic motor response stimulated by sensory information.
When blood pressure to the brain decreases, the decrease is detected by PRESSORECEPTORS located in the carotid SINUS.
Bob, a college freshman, is telling his new friends that he has been running seriously for about 6 years, and can run a marathon in a little over 3 hours. His friends aren't sure they should believe him, but don't want to spend 3 hours waiting while Bob runs 26 miles. Bob says that he can prove he is telling the truth in 1 minute. Can he? Explain why or why not. Which chamber wall of Bob's heart would you expect to be the thickest and why? =>
Yes, he can. Bob can take his pulse. A person in excellent physical condition (as one would expect Bob to be) has a slow resting pulse, because the heart is a more efficient pump and pumps more blood per beat (higher stroke volume). Therefore, it does not have to beat as many times to maintain normal cardiac output. The wall of Bob's left ventricle should be thicker. This wall is normally thicker -- more heart muscle enables the left ventricle to contract more forcefully, because it must pump blood to the entire body.
Blood pressure in the pulmonary circulation and capillaries is:
always low, to prevent filtration and accumulation of fluid in the alveoli
The left ventricle pumps blood into the ______________, to the _________________.
aorta / body
a) The effect of ANP (atrial natriuretic peptide) on the kidneys is to decrease the reabsorption of SODIUM IONS, which in turn increases the excretion of WATER.
b) The effect of ANP (atrial natriuretic peptide) on vascular smooth muscle is to cause VASODILATION.
The amount of blood pumped by the ventricle in one minute is called the:
cardiac output
Which of the following does not have capillary networks?
cartilage
Starling's law of the heart says that when cardiac muscle fibers are stretched, they will:
contract more forcefully
Velocity of blood flow is inversely related to the:
cross-sectional area of the part of the vascular system
In one cardiac cycle, when the ventricles are in systole, the atria are in:
diastole
When blood flow through the kidneys decreases:
filtration decreases and water is conserved to maintain BP
The vein that returns blood from the lower body to the right atrium is the:
inferior vena cava
The heart is ________________ to the lungs and ______________ to the diaphragm.
medial / superior
The part of the brain that regulates heart rate is the:
medulla
The ejection fraction of the heart is the:
percent of the blood within a ventricle that is pumped during systole
The carotid sinus contains:
pressoreceptors that detect changes in blood pressure
The general function of the valves of the heart is to:
prevent backflow of blood
The function of the serous fluid between the parietal pericardium and visceral pericardium is to:
prevent friction
The right ventricle pumps blood into the _____________, to the ______________.
pulmonary artery / lungs
The function of the myocardium is to:
pump blood
The effect of the hormone norepinephrine on blood pressure is to:
raise it by causing vasoconstriction
The effect of the hormone ADH on blood pressure is to:
raise it by increasing blood volume
When blood pressure decreases, the kidneys secrete _______________, which will initiate the formation of angiotensin II.
renin
Which sequence correctly describes blood flow?
right heart to lungs to left heart to body to right heart
In pulmonary circulation, blood is pumped to the lungs by the:
right ventricle
The pulmonary artery takes blood from the:
right ventricle to the lungs
The vein that returns blood from the upper body to the right atrium is the:
superior vena cava
The heart rate is increased by:
sympathetic impulses
During one cardiac cycle:
the atria contract together, followed by the ventricles contracting together
A systolic BP value is the pressure when:
the left ventricle is contracting
Capillaries are made of simple squamous epithelium because this tissue is:
thin, to permit exchanges of materials
The right and left AV valves prevent backflow of blood from the:
ventricles to the atria when the ventricles contract
The inner layer of the pericardial membranes is the:
visceral pericardium
