Learning outcomes

Question 1

Describe the main functions of the circulatory system

Question 2

Describe how oxygenated and deoxygenated blood flows through the heart

Question 3

Explain what is meant by “the systemic circulation delivers blood in parallel”

Question 4

Describe the cardiac valves and how they achieve their purpose

Question 5

Describe the unique properties of cardiac muscle cells in relation to their function

Question 6

Explain how cardiac muscle cells communicate with each other

Question 7

Describe the cardiac conduction system

Question 8

Describe the cardiac action potential and its underlying currents

Question 9

Explain the excitation-contraction coupling

Question 10

Explain what electrical activity occurs to results in the lead II ECG trace.

Question 11

Within the context of the electrical activity of the heart, describe the mechanical activity of the cardiac cycle.

Question 12

Describe why there are periods of isovolumetric concentration and relaxation

Question 13

Describe why heart sounds can be heard

Question 14

Explain how cardiac output is calculated.

Question 15

Describe the Frank-Starling law of the heart

Question 16

Explain why end diastolic volume is so important for the regulation of cardiac contractility

Question 17

Explain how cardiac output is regulated

Question 18

Describe the unique features of the coronary circulation.

Question 19

Explain the oxygen demand of the heart and how it is accommodated.

Question 20

What is the role of the heart in the circulatory system?

Answer 20

The heart serves as the central pump in the circulatory system, responsible for pumping blood throughout the entire body.

Question 21

Describe the flow of blood throughout the body.

Answer 21

Blood is pumped from the heart into arteries, which carry oxygenated blood to various tissues. In capillaries, exchange of oxygen and nutrients occurs, and deoxygenated blood returns to the heart through veins, completing the circulatory loop.

Question 22

Explain the flow of excitation and contraction during the cardiac cycle.

Answer 22

The cardiac cycle involves electrical excitation (depolarization) and contraction. The sinoatrial (SA) node initiates the heartbeat, leading to atrial contraction (P wave). After a delay at the atrioventricular (AV) node, the excitation travels to the ventricles, causing their contraction (QRS complex). Finally, the ventricles relax during repolarization (T wave).

Question 23

Explain the statement “what enters the heart, the heart pumps out.”

Answer 23

This statement emphasizes that the heart ejects the same volume of blood it receives during each cardiac cycle, ensuring a continuous flow and regulation of cardiac output.

Question 24

Identify key components of the coronary circulation.

Answer 24

Coronary circulation includes coronary arteries branching off the aorta, supplying oxygen-rich blood to the heart. During diastole, about 70% of blood flow occurs, ensuring the heart meets its high metabolic demands.