Cardiovascular Physiology: Master the Electrical and Mechanical Properties of the Heart

Question 1

Which factor directly affects the force of cardiac contraction?

Accepted Answer

Contractility

Answer

Preload

Answer

Afterload

Answer

Heart rate

Question 2

The sinoatrial (SA) node primarily functions to:

Accepted Answer

Initiate the electrical impulse for heart contractions

Answer

Transmit the electrical impulse from the atria to the ventricles

Answer

Control heart rate

Answer

Prevent backward flow of electrical impulses

Question 3

Which characteristic describes laminar blood flow in the cardiovascular system?

Accepted Answer

Parallel layers of blood movement

Answer

Faster blood flow in the center of the blood vessel compared to near the walls

Answer

Turbulent mixing

Answer

No influence of blood viscosity on flow

Question 4

The primary mechanism for regulating blood pressure is:

Accepted Answer

Systemic vascular resistance

Answer

Cardiac output

Answer

Venous return

Answer

Blood volume

Question 5

Which hormone increases both heart rate and contractile force?

Accepted Answer

Epinephrine

Answer

Acetylcholine

Answer

Norepinephrine

Answer

Dopamine

Question 6

The cardiac cycle involves which phases?

Accepted Answer

Systole and diastole

Answer

Atrial systole and ventricular systole

Answer

Diastole and atrial systole

Answer

Ventricular systole and atrial diastole

Question 7

Which factor is a major determinant of cardiac preload?

Accepted Answer

Venous return

Answer

Heart rate

Answer

Aortic pressure

Answer

Myocardial contractility

Question 8

The Frank-Starling law describes the relationship between:

Accepted Answer

Cardiac output and preload

Answer

Cardiac output and afterload

Answer

Heart rate and cardiac output

Answer

Blood pressure and systemic vascular resistance

Question 9

The normal resting adult heart rate is approximately:

Accepted Answer

60-80 beats per minute

Answer

50-60 beats per minute

Answer

80-100 beats per minute

Answer

100-120 beats per minute

Question 10

Explain the distinct roles of sodium, potassium, and calcium ion channels in the generation and propagation of the cardiac action potential.

Accepted Answer

Sodium channels trigger the upstroke, potassium channels repolarize, and calcium channels sustain the plateau.

Answer

Potassium channels trigger the upstroke, sodium channels repolarize, and calcium channels trigger the plateau.

Answer

Calcium channels trigger the upstroke, sodium channels repolarize, and potassium channels sustain the plateau.

Question 11

In familial hypercholesterolemia, which of the following is caused by mutations in the LDLR gene?

Accepted Answer

Defective LDL receptors on liver cells

Answer

Increased production of LDL particles by liver cells

Answer

Increased uptake of LDL particles by immune cells

Question 12

During which phase of the cardiac cycle do the ventricles relax and fill with blood?

Accepted Answer

Diastole

Answer

Systole

Answer

Isovolumetric contraction

Answer

Isovolumetric relaxation

Question 13

Statins are lipid-lowering medications used to prevent atherosclerosis. Which of the following best describes their primary mechanism of action?

Accepted Answer

Reducing LDL cholesterol synthesis

Answer

Increasing HDL cholesterol levels

Answer

Lowering blood pressure

Answer

Inhibiting inflammation

Question 14

Which of the following relationships describes the effect of heart rate (HR) on cardiac output (CO)?

Accepted Answer

CO is directly proportional to HR.

Answer

CO is independent of HR.

Answer

CO is inversely proportional to HR.

Question 15

What is the primary function of the sinoatrial (SA) node in the heart's electrical system?

Accepted Answer

To initiate the electrical impulse that triggers the heartbeat.

Answer

To conduct the electrical impulse to the atrioventricular (AV) node.

Answer

To regulate the heart rate in response to changes in blood pressure.

Question 16

During the cardiac action potential, which ion is primarily responsible for the rapid depolarization of cardiac muscle cells?

Accepted Answer

Sodium (Na+)

Answer

Chloride (Cl-)

Answer

Potassium (K+)

Answer

Calcium (Ca2+)

Question 17

Which of the following factors will NOT increase systemic vascular resistance (SVR)?

Accepted Answer

Increased cardiac output

Answer

Narrowing of blood vessels

Answer

Vasoconstriction

Answer

Increased blood viscosity

Question 18

What is the approximate normal systolic blood pressure in a healthy adult?

Accepted Answer

120 mmHg

Answer

160 mmHg

Answer

80 mmHg

Answer

200 mmHg

Question 19

Which of the following is the primary determinant of coronary blood flow?

Accepted Answer

Perfusion pressure

Answer

Cardiac output

Answer

Venous return

Answer

Heart rate

Question 20

What is the most common cause of secondary hypertension, a form of high blood pressure that is caused by an underlying medical condition?

Accepted Answer

Renal artery stenosis

Answer

Pheochromocytoma

Answer

Essential hypertension

Answer

Coarctation of the aorta

Question 21

Which ion is primarily responsible for the rapid depolarization phase of the cardiac action potential?

Accepted Answer

Sodium (Na+)

Answer

Calcium (Ca2+)

Answer

Potassium (K+)

Answer

Chloride (Cl-)

Question 22

What is the phenomenon where an increase in ventricular filling pressure results in an increase in cardiac output known as?

Accepted Answer

Frank-Starling mechanism

Answer

Bainbridge reflex

Answer

Bowditch effect

Answer

Treppe phenomenon

Question 23

Which type of blood vessel typically offers the least resistance to blood flow?

Accepted Answer

Capillaries

Answer

Arterioles

Answer

Veins

Answer

Arteries

Question 24

What is the primary role of the sinoatrial (SA) node?

Accepted Answer

Initiation and generation of cardiac electrical impulses

Answer

Receiving and transmitting electrical impulses to the atrioventricular (AV) node

Answer

Contraction of the atria

Question 25

How does sympathetic nervous system activity generally affect cardiac function?

Accepted Answer

Increased heart rate, contractility, and stroke volume

Answer

Increased heart rate, but decreased contractility and stroke volume

Answer

Decreased heart rate, contractility, and stroke volume

Question 26

What is the main purpose of the pulmonary circulation?

Accepted Answer

Gas exchange between blood and lungs

Answer

Nutrient delivery to tissues

Answer

Removal of waste products

Question 27

Which of the following is NOT a type of blood vessel in the cardiovascular system?

Accepted Answer

Lymph

Answer

Capillary

Answer

Vein

Answer

Artery

Question 28

Which of the following factors does NOT influence heart rate regulation?

Accepted Answer

Capillary constriction

Answer

Sympathetic nervous system stimulation

Answer

Blood pH changes

Answer

Vagus nerve stimulation

Question 29

Which factor primarily determines the volume of blood ejected per beat?

Accepted Answer

End-diastolic volume

Answer

Contractility

Answer

Aortic pressure

Answer

Sympathetic tone

Question 30

Which hormone is known to induce vasoconstriction?

Accepted Answer

Epinephrine

Answer

Nitric oxide

Answer

Prostacyclin

Answer

Bradykinin

Question 31

What is the most prevalent cause of cardiogenic shock?

Accepted Answer

Acute myocardial infarction

Answer

Anaphylaxis

Answer

Sepsis

Question 32

Which of the following is a modifiable risk factor for developing coronary artery disease?

Accepted Answer

Smoking

Answer

Low blood pressure

Answer

Normal cholesterol levels

Answer

Frequent exercise

Question 33

What is the term for the stable electrical state of ventricular myocardial cells?

Accepted Answer

Phase 4 depolarization

Answer

Phase 3 repolarization

Answer

Phase 1 repolarization

Answer

Phase 0 depolarization

Question 34

What anatomical structure separates the heart's atria from ventricles?

Accepted Answer

Atrioventricular valves

Answer

Semilunar valves

Answer

Papillary muscles

Answer

Chordae tendineae

Question 35

Identify the primary determinant of myocardial oxygen consumption.

Accepted Answer

Wall stress

Answer

Preload

Answer

Heart rate

Answer

Cardiac output

Question 36

Which factor plays a pivotal role in regulating preload in the heart?

Accepted Answer

Venous return

Answer

Heart rate

Answer

Afterload

Answer

Cardiac contractility

Question 37

The baroreflex primarily functions to regulate:

Accepted Answer

Blood pressure

Answer

Cardiac output

Answer

Stroke volume

Answer

Heart rate

Question 38

Laminar blood flow is distinguished by:

Accepted Answer

Smooth, parallel movement of blood layers

Answer

Parabolic velocity profile

Answer

Resistance directly proportional to velocity

Answer

Turbulent flow patterns

Question 39

The cardiac conduction system's primary function is to:

Accepted Answer

Coordinate and initiate cardiac contractions

Answer

Control blood pressure

Answer

Pump blood to the lungs

Answer

Regulate electrolyte balance

Question 40

During exercise, vasodilation in skeletal muscle is predominantly caused by:

Accepted Answer

Release of nitric oxide

Answer

Sympathetic nervous system activation

Answer

Increased blood viscosity

Question 41

The forces governing transcapillary fluid exchange, as per the Starling principle, are primarily determined by:

Accepted Answer

Hydrostatic and osmotic pressures

Answer

Cardiac output and blood flow

Answer

Arterial and venous pressures

Answer

Respiratory rate and tidal volume

Question 42

Which of the following properties is NOT characteristic of cardiac muscle?

Accepted Answer

It is excitable but not contractile

Answer

It is striated and involuntary

Answer

It contains intercalated discs

Question 43

The standard electrocardiogram (ECG) complex comprises which of the following waves in sequence?

Accepted Answer

P wave, QRS complex, and T wave

Answer

Q wave, R wave, and T wave

Answer

P wave, S wave, and U wave

Answer

R wave, S wave, and P wave

Question 44

The primary function of the heart is to:

Accepted Answer

Pump blood throughout the body

Answer

Regulate blood pressure

Answer

Exchange gases between the blood and the lungs

Answer

Filter waste products from the blood

Question 45

Which of the following combinations of factors can result in an increase in blood pressure?

Accepted Answer

Increased cardiac output and increased peripheral resistance

Answer

Decreased cardiac output and decreased peripheral resistance

Answer

Increased cardiac output and decreased peripheral resistance

Answer

Decreased cardiac output and increased peripheral resistance

Question 46

The cardiac cycle can be divided into which two main phases?

Accepted Answer

Systole and diastole

Answer

Conduction and refractory periods

Answer

Atrial contraction and ventricular relaxation

Answer

Ischemia and reperfusion

Question 47

Which of the following structures receives its blood supply from the coronary arteries?

Accepted Answer

Myocardium

Answer

Endocardium

Answer

Epicardium

Answer

Pericardium

Question 48

Which of the following hormones has both a positive chronotropic (heart rate increasing) and a positive inotropic (contractility increasing) effect on the heart?

Accepted Answer

Epinephrine

Answer

Glucagon

Answer

Insulin

Answer

Aldosterone

Question 49

The sinoatrial node (SA node) is primarily responsible for:

Accepted Answer

Generating the electrical impulses that initiate each heartbeat

Answer

Stopping electrical impulses from propagating through the heart

Answer

Delaying electrical impulses before they reach the ventricles

Answer

Conducting electrical impulses from the atria to the ventricles

Question 50

Which of the following is a well-established risk factor for the development of cardiovascular disease?

Accepted Answer

Smoking

Answer

Adequate sleep duration

Answer

Regular exercise

Answer

A balanced and nutritious diet

Question 51

The lymphatic system plays a crucial role in:

Accepted Answer

Clearing excess fluid and waste products from tissues

Answer

Regulating body temperature

Answer

Transporting nutrients and oxygen to cells