Question 1

A condition in which the heart is contracting in an uncontrolled, rapid, and irregular manner:

Accepted Answer

A)  is heart block 
B)  is fibrillation 
C)  can be treated with administration of an electrical current 
D)  is heart block and fibrillation 
E)  is fibrillation and can be treated with administration of an electrical current 
A)  is heart block 
B)  is fibrillation 
C)  can be treated with administration of an electrical current 
D)  is heart block and fibrillation 
E)  is fibrillation and can be treated with administration of an electrical current E

Question 2

Diastole refers to the period of cardiac repolarization.

Accepted Answer

A) True 
 B)False  False

Question 3

The right ventricle pumps deoxygenated blood through the tricuspid valve and into the pulmonary arteries.

Accepted Answer

A) True 
 B)False  False

Question 4

Complete each of the following statements with increases, decreases, or has no effect on.
Decreasing preload ____________________ contractility, which then ____________________ stroke volume.

Accepted Answer

decreases,

Question 5

The mitral valve prevents regurgitation of blood back into the left atrium from the left ventricle.

Accepted Answer

A) True 
 B)False

Question 6

The primary function of the pericardial sac is to

Accepted Answer

A)  prevent excessive expansion of the heart as it fills with blood 
B)  secrete a fluid that reduces friction as the heart beats 
C)  serve as a reservoir for blood to be used during strenuous exercise 
D)  provide oxygen and nutrients to the heart muscle 
E)  catch and kill any bacteria in the blood flowing through the heart chambers 
A)  prevent excessive expansion of the heart as it fills with blood 
B)  secrete a fluid that reduces friction as the heart beats 
C)  serve as a reservoir for blood to be used during strenuous exercise 
D)  provide oxygen and nutrients to the heart muscle 
E)  catch and kill any bacteria in the blood flowing through the heart chambers

Question 7

On a normal ECG, a wave for repolarization of the atria is not recorded. Why?

Accepted Answer

A)  The leads are not placed in a position to pick it up. 
B)  No repolarization of the atria occurs normally. 
C)  It occurs simultaneously with ventricular depolarization and is masked by the QRS complex. 
D)  It does not travel through body fluids. 
E)  It is too small to be picked up by external recording electrodes. 
A)  The leads are not placed in a position to pick it up. 
B)  No repolarization of the atria occurs normally. 
C)  It occurs simultaneously with ventricular depolarization and is masked by the QRS complex. 
D)  It does not travel through body fluids. 
E)  It is too small to be picked up by external recording electrodes.

Question 8

The cardiac muscle

Accepted Answer

A)  extracts oxygen and nutrients from the blood within its chambers 
B)  receives its blood supply primarily during ventricular systole when blood is forced into the vessels supplying the heart 
C)  receives its blood supply as all blood returning to the heart from the lung passes through the cardiac circulation before being pumped to the systemic circulation 
D)  receives most of its blood supply during ventricular diastole by means of the coronary circulation 
E)  none of these 
A)  extracts oxygen and nutrients from the blood within its chambers 
B)  receives its blood supply primarily during ventricular systole when blood is forced into the vessels supplying the heart 
C)  receives its blood supply as all blood returning to the heart from the lung passes through the cardiac circulation before being pumped to the systemic circulation 
D)  receives most of its blood supply during ventricular diastole by means of the coronary circulation 
E)  none of these

Question 9

When the heart is sympathetically stimulated,

Accepted Answer

A)  ESV will increase. 
B)  It is responding to acetylcholine. 
C)  It is responding to norepinephrine. 
D)  Ca2+ channels are opening in greater numbers. 
E)  It is responding to norepinephrine, and Ca2+ channels are opening in greater numbers. 
A)  ESV will increase. 
B)  It is responding to acetylcholine. 
C)  It is responding to norepinephrine. 
D)  Ca2+ channels are opening in greater numbers. 
E)  It is responding to norepinephrine, and Ca2+ channels are opening in greater numbers.

Question 10

During isovolumetric phases of the cardiac cycle,

Accepted Answer

A)  The atria are contracting. 
B)  All heart valves are closed. 
C)  Blood is being ejected into the aorta. 
D)  The ventricles can only be relaxing. 
E)  The atria are contracting and all heart valves are closed. 
A)  The atria are contracting. 
B)  All heart valves are closed. 
C)  Blood is being ejected into the aorta. 
D)  The ventricles can only be relaxing. 
E)  The atria are contracting and all heart valves are closed.

Question 11

Complete each of the following statements with increases, decreases, or has no effect on.
Increasing stroke volume ____________________ cardiac output.

Accepted Answer

The answer of Complete each of the following statements with...

Question 12

Which of the following statements about action potentials in the heart is correct?

Accepted Answer

A)  The rising phase of the action potential in autorhythmic cells is due to a rapid Ca2+ influx. 
B)  The rising phase of the action potential in contractile cells is due to a rapid Na+ influx. 
C)  The plateau phase of the action potential in contractile cells is due to a slow Ca2+ influx. 
D)  The rising phase of the action potential in autorhythmic cells is due to a rapid Ca2+ influx, and the rising phase of the action potential in contractile cells is due to a rapid Na+ influx 
E)  all of these 
A)  The rising phase of the action potential in autorhythmic cells is due to a rapid Ca2+ influx. 
B)  The rising phase of the action potential in contractile cells is due to a rapid Na+ influx. 
C)  The plateau phase of the action potential in contractile cells is due to a slow Ca2+ influx. 
D)  The rising phase of the action potential in autorhythmic cells is due to a rapid Ca2+ influx, and the rising phase of the action potential in contractile cells is due to a rapid Na+ influx 
E)  all of these

Question 13

The refractory period in cardiac muscle is much shorter than the refractory period in skeletal muscle to ensure that the heart can quickly be re-stimulated to produce alternate periods of contraction and relaxation.

Accepted Answer

A) True 
 B)False

Question 14

The refractory period of cardiac muscle

Accepted Answer

A)  lasts almost as long as the contraction period 
B)  is much longer than the refractory period in skeletal muscle 
C)  prevents tetanic contraction of the heart to occur to ensure smooth, coordinated ejection of blood from the ventricles 
D)  all of these 
E)  lasts almost as long as the contraction period and is much longer than the refractory period in skeletal muscle 
A)  lasts almost as long as the contraction period 
B)  is much longer than the refractory period in skeletal muscle 
C)  prevents tetanic contraction of the heart to occur to ensure smooth, coordinated ejection of blood from the ventricles 
D)  all of these 
E)  lasts almost as long as the contraction period and is much longer than the refractory period in skeletal muscle

Question 15

An increased heart rate can result due to a decrease in parasympathetic stimulation or an increase in sympathetic stimulation of the heart.

Accepted Answer

A) True 
 B)False

Question 16

Complete each of the following statments.
____________________ carries cholesterol to cells, whereas ____________________ transports it away from cells.

Accepted Answer

The answer of Complete each of the following statments.
____________________ carries...

Question 17

Under normal conditions, all of the EDV is ejected before ventricular diastole begins.

Accepted Answer

A) True 
 B)False

Question 18

The plateau of the cardiac action potential results from the opening of voltage-gated slow ____ channels in the plasma membrane of the ____ cell.

Accepted Answer

A)  sodium; contractile 
B)  potassium; autorhythmic 
C)  calcium; contractile 
D)  chloride; pacemaker 
E)  potassium; contractile 
A)  sodium; contractile 
B)  potassium; autorhythmic 
C)  calcium; contractile 
D)  chloride; pacemaker 
E)  potassium; contractile

Question 19

Ventricular ejection occurs once the afterload has been overcome.

Accepted Answer

A) True 
 B)False

Question 20

Complete each of the following statements with increases, decreases, or has no effect on.
An increase in parasympathetic activity ____________________ the atrial contractility.

Accepted Answer

The answer of Complete each of the following statements with...

Exam 9: A--Cardiac Physiology

A condition in which the heart is contracting in an uncontrolled, rapid, and irregular manner:

Diastole refers to the period of cardiac repolarization.

The right ventricle pumps deoxygenated blood through the tricuspid valve and into the pulmonary arteries.

Complete each of the following statements with increases, decreases, or has no effect on. Decreasing preload ____________________ contractility, which then ____________________ stroke volume.

The mitral valve prevents regurgitation of blood back into the left atrium from the left ventricle.

The primary function of the pericardial sac is to

On a normal ECG, a wave for repolarization of the atria is not recorded. Why?

The cardiac muscle

When the heart is sympathetically stimulated,

During isovolumetric phases of the cardiac cycle,

Complete each of the following statements with increases, decreases, or has no effect on. Increasing stroke volume ____________________ cardiac output.

Which of the following statements about action potentials in the heart is correct?

The refractory period in cardiac muscle is much shorter than the refractory period in skeletal muscle to ensure that the heart can quickly be re-stimulated to produce alternate periods of contraction and relaxation.

The refractory period of cardiac muscle

An increased heart rate can result due to a decrease in parasympathetic stimulation or an increase in sympathetic stimulation of the heart.

Complete each of the following statments. ____________________ carries cholesterol to cells, whereas ____________________ transports it away from cells.

Under normal conditions, all of the EDV is ejected before ventricular diastole begins.

The plateau of the cardiac action potential results from the opening of voltage-gated slow ____ channels in the plasma membrane of the ____ cell.

Ventricular ejection occurs once the afterload has been overcome.

Complete each of the following statements with increases, decreases, or has no effect on. An increase in parasympathetic activity ____________________ the atrial contractility.

Introduction to Physiology and Homeostasis

Cell Physiology

The Plasma Membrane and Membrane Potential

Principles of Neural and Hormonal Communication

A--The Central Nervous System

B--The Central Nervous System

A--The Peripheral Nervous System: Afferent Division; Special Senses

B--The Peripheral Nervous System: Afferent Division; Special Senses

The Peripheral Nervous System: Efferent Division

A--Muscle Physiology

B--Muscle Physiology

B--Cardiac Physiology

The Blood Vessels and Blood Pressure

The Blood

Body Defenses

A--The Respiratory System

B--The Respiratory System

A--The Urinary System

B--The Urinary System

A--Fluid and Acid-Base Balance

B--Fluid and Acid-Base Balance

A--The Digestive System

B--The Digestive System

Energy Balance and Temperature Regulation

A--Principles of Endocrinology: the Central Endocrine Glands

B--Principles of Endocrinology: the Central Endocrine Glands

A--The Peripheral Endocrine Glands

B--The Peripheral Endocrine Glands

A--The Reproductive System

B--The Reproductive System

Filters

Complete each of the following statements with increases, decreases, or has no effect on. Decreasing preload contractility, which then stroke volume.

Complete each of the following statments. carries cholesterol to cells, whereas transports it away from cells.

The plateau of the cardiac action potential results from the opening of voltage-gated slow channels in the plasma membrane of the cell.