Week 7 - The Cardiovascular System

Question 1

What are the five main types of blood vessels in the cardiovascular system?

Answer 1

Arteries, arterioles, capillaries, venules, veins.

Question 2

What is the function of arteries?

Answer 2

Carry blood away from the heart (usually oxygenated).

Question 3

What is the function of arterioles?

Answer 3

Regulate blood flow and pressure; lead into capillaries.

Question 4

What is the function of capillaries?

Answer 4

Allow exchange of gases, nutrients, and waste between blood and tissues.

Question 5

What is the function of venules?

Answer 5

Collect blood from capillaries and begin return flow to the heart.

Question 6

What is the function of veins?

Answer 6

Return blood to the heart (usually deoxygenated); contain valves.

Question 7

What are the three tunics of blood vessels (excluding capillaries)?

Answer 7

Tunica intima, tunica media, tunica externa.

Question 8

What are the structural features of arteries?

Answer 8

Thick tunica media, smaller lumen, all three tunics, elastic and muscular types.

Question 9

What are the structural features of arterioles?

Answer 9

Small vessels with thick walls, all three tunics, regulate blood flow via vasoconstriction/dilation.

Question 10

What are the structural features of capillaries?

Answer 10

Only endothelial layer and basement membrane.

Question 11

Name and describe the three types of capillaries.

Answer 11

Continuous (tight junctions), fenestrated (pores), sinusoids (large gaps, incomplete basement).

Question 12

What are the structural features of venules?

Answer 12

Vary by type; postcapillary (endothelium + pericytes), muscular (thin tunica media).

Question 13

What are the structural features of veins?

Answer 13

Thinner walls, larger lumen, valves, all three tunics, blood reservoirs.

Question 14

Name the four chambers of the heart.

Answer 14

Right atrium, right ventricle, left atrium, left ventricle.

Question 15

Name the four valves of the heart.

Answer 15

Tricuspid, pulmonary, mitral (bicuspid), aortic.

Question 16

Which vessels bring deoxygenated blood to the right atrium?

Answer 16

Superior and inferior vena cava.

Question 17

Which vessels return oxygenated blood from lungs to the heart?

Answer 17

Pulmonary veins (left and right).

Question 18

What vessel distributes oxygenated blood from the heart to the body?

Answer 18

Aorta.

Question 19

What arteries supply the heart muscle itself?

Answer 19

Coronary arteries.

Question 20

What are the three layers of the heart wall from inside to outside?

Answer 20

Endocardium, myocardium, epicardium.

Question 21

What is the function of the myocardium?

Answer 21

Cardiac muscle responsible for heart contractions.

Question 22

What is the function of the pericardium?

Answer 22

Protects and anchors the heart; allows friction-free movement.

Question 23

Describe pulmonary circulation.

Answer 23

Right ventricle → pulmonary arteries → lungs → pulmonary veins → left atrium.

Question 24

Describe systemic circulation.

Answer 24

Left ventricle → aorta → body → vena cavae → right atrium.

Question 25

What is the role of the SA node?

Answer 25

Acts as pacemaker; generates action potentials in the right atrium.

Question 26

What is the role of the AV node?

Answer 26

Delays impulse to allow atria to contract before ventricles.

Question 27

What does the Bundle of His do?

Answer 27

Transmits impulses from the AV node to the ventricles.

Question 28

What is the function of the Purkinje fibers?

Answer 28

Distribute impulses to the ventricular myocardium, triggering contraction.

Question 29

What is blood pressure (BP)?

Answer 29

The force exerted by blood on vessel walls.

Question 30

What is systolic pressure?

Answer 30

Highest pressure during ventricular contraction.

Question 31

What is diastolic pressure?

Answer 31

Lowest pressure during ventricular relaxation.

Question 32

How is mean arterial pressure (MAP) calculated?

Answer 32

MAP = Diastolic + 1/3(Systolic - Diastolic)

Question 33

What is end diastolic volume (EDV)?

Answer 33

Volume of blood in ventricles before contraction.

Question 34

What is end systolic volume (ESV)?

Answer 34

Volume of blood left in ventricles after contraction.

Question 35

How is stroke volume (SV) calculated?

Answer 35

SV = EDV - ESV

Question 36

What is ejection fraction?

Answer 36

(SV ÷ EDV) × 100; percentage of EDV ejected per beat.

Question 37

What increases mean arterial pressure (MAP)?

Answer 37

Increased cardiac output (CO) or vascular resistance.

Question 38

What three factors increase vascular resistance?

Answer 38

Smaller vessel diameter, increased blood viscosity, longer vessel length.

Question 39

What is the formula for cardiac output (CO)?

Answer 39

CO = Stroke Volume × Heart Rate

Question 40

What are baroreceptors?

Answer 40

Mechanoreceptors that detect changes in blood pressure via vessel stretch.

Question 41

Where are baroreceptors located?

Answer 41

Carotid sinus (brain) and aortic arch (body).

Question 42

How do baroreceptors respond to high BP?

Answer 42

Increase firing → decreased heart rate → vasodilation → lower BP.

Question 43

How do baroreceptors respond to low BP?

Answer 43

Decrease firing → increased heart rate → vasoconstriction → raise BP.