Question 1

Which of the following is NOT a function of the cardiovascular system?

Accepted Answer

Synthesizes hormones

Question 2

The heart is located in which anatomical region of the thoracic cavity?

Accepted Answer

Mediastinum

Question 3

Which layer of the heart wall is responsible for the contractile force of the heart?

Accepted Answer

Myocardium

Question 4

What is the primary function of the intercalated discs in cardiac muscle cells?

Accepted Answer

Allow ions to flow between cells for synchronized contraction

Question 5

Which of the following correctly describes the flow of blood through the heart?

Accepted Answer

Right atrium → right ventricle → pulmonary trunk

Question 6

During ventricular relaxation, which valves are open and which are closed?

Accepted Answer

AV valves open, semilunar valves closed

Question 7

A blockage in the left coronary artery is most likely to result in which clinical condition?

Accepted Answer

Myocardial infarction

Question 8

Which risk factor is NOT associated with coronary atherosclerosis?

Accepted Answer

High fiber diet

Question 9

The pacemaker of the heart is the:

Accepted Answer

SA node

Question 10

Which of the following best describes the refractory period in cardiac muscle cells?

Accepted Answer

The time after a cell has responded to a stimulus and cannot be re-excited

Question 11

Which equation best represents the rapid depolarization phase of a cardiac myocyte action potential?

Accepted Answer

$$\Delta V = V_{Na^+}$$

Question 12

If the SA node is damaged, which structure typically takes over as the pacemaker, and what is the expected heart rate?

Accepted Answer

AV node; 40-50 bpm

Question 13

Which of the following is a direct result of the heart’s long refractory period?

Accepted Answer

Prevents tetanic contractions

Question 14

Which of the following is TRUE regarding the structure of cardiac muscle cells?

Accepted Answer

They contain large mitochondria and are fatigue resistant

Question 15

Which valve prevents backflow of blood from the left ventricle into the left atrium?

Accepted Answer

Mitral (bicuspid) valve

Question 16

A patient presents with chest pain radiating down the left arm. Which condition is most likely responsible?

Accepted Answer

Myocardial infarction

Question 17

Which of the following best describes the role of the coronary sinus?

Accepted Answer

Returns deoxygenated coronary blood to the right atrium

Question 18

Which of the following is a plausible consequence of a prolonged refractory period in cardiac muscle?

Accepted Answer

Prevention of tetanus and maintenance of rhythmic contractions

Question 19

Which of the following is the correct sequence of events during the action potential of a cardiac myocyte?

Accepted Answer

Na$$^+$$ channels open, rapid depolarization, Na$$^+$$ channels close, slow Ca$$^{2+}$$ channels open, Ca$$^{2+}$$ channels close, K$$^+$$ channels open

Question 20

Which of the following is a real-world example of a condition that can trigger premature ventricular contraction (PVC)?

Accepted Answer

Electrolyte imbalance

Chapter 18: Heart Part 1

Study Guide - Practice Questions

Study Guide - Flashcards