Question 1

Given end- diastolic volume = 130 mL and end- systolic volume = 50 mL, what is the stroke volume and ejection fraction?

Accepted Answer

A) SV = 180 mL, EF = 0.38 
B) SV = 80 mL, EF = 0.61 
C) SV = 80 mL, EF = 0.38 
D) SV = 180 mL, EF = 0.61 
E) SV = 50 mL, EF = 0.61 
A) SV = 180 mL, EF = 0.38 
B) SV = 80 mL, EF = 0.61 
C) SV = 80 mL, EF = 0.38 
D) SV = 180 mL, EF = 0.61 
E) SV = 50 mL, EF = 0.61 B

Question 2

Cardiac output is in part determined by changes in heart rate. Describe the factors that are responsible for inducing changes in heart rate.

Accepted Answer

Heart rate is one of the determinants of cardiac output. The heart rate is determined by the pacemaker cells. Typically, heart beats originate from the sinoatrial node. However, other sites along the conduction pathway also contain pacemaker cells that, while they tend to have a slower rate of depolarization, can also cause contraction. The ability of these cells to generate an action potential involves the slow depolarization driven by the closure of K+ channels, the opening of non- selective cation channels (funny channels)and the ultimate opening of the Ca2+ channels. The autonomic nervous system is the primary modulator of heart rate. This means that activity of sympathetic and parasympathetic neurons must be able to alter the slope of the slow depolarization of the pacemaker cells. There are sympathetic and parasympathetic neurons that innervate the sinoatrial node, atrioventricular node, and other regions of the conduction pathway that can alter heart rate. Increases in sympathetic activity will increase the slope of the slow depolarization, causing heart rate to increase, whereas parasympathetic activity will decrease the slope of the slow depolarization, causing heart rate to decrease. A number of hormones like epinephrine, glucagon, thyroid hormone, and others act in a manner similar to sympathetic activity. Each of the hormones elevates heart rate by increasing the slope of the slow depolarization. Heart rate independent of the autonomic nervous system tends to be around 100 bts/min. Since normal heart rate for adults tends to be less than that, the heart is said to be under resting parasympathetic tone. However, this is not to say that the sympathetic nervous system is not active.

Question 3

Although blood is a fluid, nearly half its volume is composed of cells. The most numerous cells are . The remainder of the cells are _ , which help the body defend itself against foreign particles and microorganisms.

Accepted Answer

A) platelets : leukocytes 
B) erythrocytes : leukocytes 
C) leukocytes : erythrocytes 
D) erythrocytes : platelets 
A) platelets : leukocytes 
B) erythrocytes : leukocytes 
C) leukocytes : erythrocytes 
D) erythrocytes : platelets B

Question 4

The second heart sound coincides with the beginning of which period in the cardiac cycle?

Accepted Answer

A) atrial contraction 
B) ventricular filling 
C) isovolumetric contraction 
D) isovolumetric relaxation 
E) ventricular ejection 
A) atrial contraction 
B) ventricular filling 
C) isovolumetric contraction 
D) isovolumetric relaxation 
E) ventricular ejection

Question 5

The increased aortic pressure that occurs during systole reflects a(n)

Accepted Answer

A) decreased volume of blood within the aorta. 
B) decreased resistance of the vasculature. 
C) decreased stiffness of the aorta. 
D) increased volume of blood in the aorta. 
E) increased resistance of the vasculature. 
A) decreased volume of blood within the aorta. 
B) decreased resistance of the vasculature. 
C) decreased stiffness of the aorta. 
D) increased volume of blood in the aorta. 
E) increased resistance of the vasculature.

Question 6

The preload is approximately the same as the pressure.

Accepted Answer

A) aortic diastolic 
B) end- systolic 
C) atrial 
D) aortic systolic 
E) end- diastolic 
A) aortic diastolic 
B) end- systolic 
C) atrial 
D) aortic systolic 
E) end- diastolic

Question 7

Normal resting heart rate is around 70 beats per minute due to the SA node. If the SA node fails, what would you expect the heart beats per minute to be?

Accepted Answer

A) If the SA node fails the individual will go into heart failure and therefore there will be no heart rate. 
B) 30- 40 beats per minute 
C) 50 beats per minute 
D) 10- 20 beats per minute 
E) 70 beats per minute as the AV node takes over for the SA node 
A) If the SA node fails the individual will go into heart failure and therefore there will be no heart rate. 
B) 30- 40 beats per minute 
C) 50 beats per minute 
D) 10- 20 beats per minute 
E) 70 beats per minute as the AV node takes over for the SA node

Question 8

If damage to the AV node slowed down conduction through this tissue, what would be observed on an ECG?

Accepted Answer

A) an inverted T wave 
B) a longer PR interval 
C) a larger P wave 
D) a wider QRS complex 
E) a longer P wave 
A) an inverted T wave 
B) a longer PR interval 
C) a larger P wave 
D) a wider QRS complex 
E) a longer P wave

Question 9

Which component of an ECG represents ventricular diastole?

Accepted Answer

A) T wave 
B) P- R interval 
C) Q- T interval 
D) T- Q segment 
E) QRS complex 
A) T wave 
B) P- R interval 
C) Q- T interval 
D) T- Q segment 
E) QRS complex

Question 10

The pathway by which action potentials from the sinoatrial node travel through the heart is important for the normal function of the heart. Describe the conduction pathway of the heart and how that path corresponds to electrical events in an ECG reading.

Accepted Answer

The autorhythmicity of the pacemaker cel

Question 11

Which statement best describes parallel flow in the circulatory system?

Accepted Answer

A) In the systemic circuit blood flows from one organ directly to the next, hence in parallel. 
B) Parallel flow refers to the flow of blood just to the heart itself, which keeps it oxygenated at all times. 
C) Parallel flow refers to deoxygenated blood only and not to oxygenated blood. 
D) Parallel flow refers to the flow of electrical impulses in the heart. 
E) The organs of the body are arranged in a parallel circuit to allow adequate flow and pressure to all body systems and maintain homeostasis of blood pressure. 
A) In the systemic circuit blood flows from one organ directly to the next, hence in parallel. 
B) Parallel flow refers to the flow of blood just to the heart itself, which keeps it oxygenated at all times. 
C) Parallel flow refers to deoxygenated blood only and not to oxygenated blood. 
D) Parallel flow refers to the flow of electrical impulses in the heart. 
E) The organs of the body are arranged in a parallel circuit to allow adequate flow and pressure to all body systems and maintain homeostasis of blood pressure.

Question 12

The circulatory system consists of two divisions and is supplied with blood by different sides of the heart. The right heart supplies blood to the _ circuit, whereas the left heart supplies blood to the circuit.

Accepted Answer

A) arterial : venule 
B) systemic : pulmonary 
C) superior (upper body): inferior (lower body) 
D) oxygenated : deoxygenated 
E) pulmonary : systemic 
A) arterial : venule 
B) systemic : pulmonary 
C) superior (upper body): inferior (lower body) 
D) oxygenated : deoxygenated 
E) pulmonary : systemic

Question 13

During isovolumetric contraction, which chamber has the greatest pressure?

Accepted Answer

A) right atrium 
B) left ventricle 
C) left atrium 
D) right ventricle 
E) AV bundle (bundle of His) 
A) right atrium 
B) left ventricle 
C) left atrium 
D) right ventricle 
E) AV bundle (bundle of His)

Question 14

Which of the following describes second- degree heart block?

Accepted Answer

A) There is a longer delay between atrial contraction and ventricular contraction. 
B) The ventricles no longer contract. 
C) Not every ventricular contraction is preceded by an atrial contraction. 
D) The atria no longer contract. 
E) Not every atrial contraction is followed by a ventricular contraction. 
A) There is a longer delay between atrial contraction and ventricular contraction. 
B) The ventricles no longer contract. 
C) Not every ventricular contraction is preceded by an atrial contraction. 
D) The atria no longer contract. 
E) Not every atrial contraction is followed by a ventricular contraction.

Question 15

Which of the following best describes the effect of sympathetic activity on ventricular contractile cells?

Accepted Answer

A) The rates of contraction and relaxation both decrease, whereas the force of contraction increases. 
B) The force of contraction increases, whereas the rates of contraction and relaxation are not affected. 
C) The rates of contraction and relaxation and the force of contraction all increase. 
D) The rate of contraction and the force of contraction both increase, whereas the rate of relaxation decreases. 
E) The rates of contraction and relaxation both increase, whereas the force of contraction decreases. 
A) The rates of contraction and relaxation both decrease, whereas the force of contraction increases. 
B) The force of contraction increases, whereas the rates of contraction and relaxation are not affected. 
C) The rates of contraction and relaxation and the force of contraction all increase. 
D) The rate of contraction and the force of contraction both increase, whereas the rate of relaxation decreases. 
E) The rates of contraction and relaxation both increase, whereas the force of contraction decreases.

Question 16

The muscular wall of the right ventricle is thicker than that of the left ventricle because it develops a greater pressure in order to deliver blood to the organs of the body.

Accepted Answer

A) True 
 B)False

Question 17

The end- diastolic volume minus the end- systolic volume is the

Accepted Answer

A) stroke volume. 
B) total ventricular volume. 
C) total atrial volume. 
D) ejection fraction. 
E) cardiac output. 
A) stroke volume. 
B) total ventricular volume. 
C) total atrial volume. 
D) ejection fraction. 
E) cardiac output.

Question 18

Under resting conditions, heart rate is primarily under the control of what control system?

Accepted Answer

A) the parasympathetic nervous system 
B) intrinsic mechanisms 
C) epinephrine 
D) the sympathetic nervous system 
E) the somatic nervous system 
A) the parasympathetic nervous system 
B) intrinsic mechanisms 
C) epinephrine 
D) the sympathetic nervous system 
E) the somatic nervous system

Question 19

The primary site of exchange between blood and interstitial fluid occurs across what type of blood vessel?

Accepted Answer

A) venules 
B) capillaries 
C) arterioles 
D) veins 
E) arteries 
A) venules 
B) capillaries 
C) arterioles 
D) veins 
E) arteries

Question 20

Which of the following components of an ECG represents ventricular depolarization?

Accepted Answer

A) P wave 
B) QRS complex 
C) T wave 
D) PQ interval 
E) TQ segment 
A) P wave 
B) QRS complex 
C) T wave 
D) PQ interval 
E) TQ segment

Exam 13: The Cardiovascular System: Cardiac Function

Given end- diastolic volume = 130 mL and end- systolic volume = 50 mL, what is the stroke volume and ejection fraction?

Cardiac output is in part determined by changes in heart rate. Describe the factors that are responsible for inducing changes in heart rate.

Although blood is a fluid, nearly half its volume is composed of cells. The most numerous cells are . The remainder of the cells are _ , which help the body defend itself against foreign particles and microorganisms.

The second heart sound coincides with the beginning of which period in the cardiac cycle?

The increased aortic pressure that occurs during systole reflects a(n)

The preload is approximately the same as the pressure.

Normal resting heart rate is around 70 beats per minute due to the SA node. If the SA node fails, what would you expect the heart beats per minute to be?

If damage to the AV node slowed down conduction through this tissue, what would be observed on an ECG?

Which component of an ECG represents ventricular diastole?

The pathway by which action potentials from the sinoatrial node travel through the heart is important for the normal function of the heart. Describe the conduction pathway of the heart and how that path corresponds to electrical events in an ECG reading.

Which statement best describes parallel flow in the circulatory system?

The circulatory system consists of two divisions and is supplied with blood by different sides of the heart. The right heart supplies blood to the _ circuit, whereas the left heart supplies blood to the circuit.

During isovolumetric contraction, which chamber has the greatest pressure?

Which of the following describes second- degree heart block?

Which of the following best describes the effect of sympathetic activity on ventricular contractile cells?

The muscular wall of the right ventricle is thicker than that of the left ventricle because it develops a greater pressure in order to deliver blood to the organs of the body.

The end- diastolic volume minus the end- systolic volume is the

Under resting conditions, heart rate is primarily under the control of what control system?

The primary site of exchange between blood and interstitial fluid occurs across what type of blood vessel?

Which of the following components of an ECG represents ventricular depolarization?

Introduction to Physiology

The Cell: Structure and Function

Cell Metabolism

Cell Membrane Transport

Chemical Messengers

The Endocrine System: Endocrine Glands and Hormone Actions

Nerve Cells and Electrical Signaling

Synaptic Transmission and Neural Integration

The Nervous System: Central Nervous System

The Nervous System: Sensory Systems

The Nervous System: Autonomic and Motor Systems

Muscle Physiology

The Cardiovascular System: Blood Vessels, Blood Flow, and Blood Pressure

The Cardiovascular System: Blood

The Respiratory System: Pulmonary Ventilation

The Respiratory System: Gas Exchange and the Regulation of Breathing

The Urinary System: Renal Function

The Urinary System: Fluid and Electrolyte Balance

The Gastrointestinal System

The Endocrine System: Regulation of Energy Metabolism and Growth

The Reproductive System

The Immune System

Diabetes Mellitus

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