Principles Circulatory System

Question 1

What are the 2 main circulations?

Answer 1

Pulmonary and Systemic

Question 2

Where does the pulmonary circulation go?

Answer 2

From the right side of the heart to the lungs

Question 3

Where does the systemic circulation go?

Answer 3

From the left side of the heart to all body tissues

Question 4

What is the average pulse rate?

Answer 4

70bpm

Question 5

What are the 3 layers of the heart?

Answer 5

Epicardium, myocardium and endocardium

Question 6

What is the epicardium?

Answer 6

Visceral serous pericardium

Question 7

What is the myocardium?

Answer 7

The middle muscular layer

Question 8

What is the endocardium?

Answer 8

It is continuous with endothelium of blood vessels

Question 9

What does the pulmonary trunk divide into?

Answer 9

Right and left pulmonary arteries

Question 10

What do cardiac valves ensure?

Answer 10

Unidirectional flow

Question 11

What layers are most blood vessels comprised of?

Answer 11

1. Tunica intima (internal) - endothelium
2. Tunica media (middle) – smooth muscles and elastic fibres
3. Tunica adventitia (external) – connective tissue

Question 12

What do ‘common’ and ‘trunk’ indicate?

Answer 12

That the artery will definitely divide again?

Question 13

What does bifurcate mean?

Answer 13

Splits into 2

Question 14

Where are arteries usually located?

Answer 14

Deeper than veins

Question 15

What does vasodilation mean?

Answer 15

Relaxation of the smooth muscle and widening of the lumen to INCREASE blood flow to the organ/tissue supplied

Question 16

What does vasoconstriction mean?

Answer 16

Contraction of smooth muscle to REDUCE blood flow to the organ/tissue supplied

Question 17

What is the sympathetic tone?

Answer 17

Background, low level of contraction of smooth muscle in arterioles

Question 18

What causes the sympathetic tone?

Answer 18

The tonic (continuous) conduction of action potentials to arterioles by sympathetic nerves

Question 19

Fun fact

Answer 19

Arteriolar smooth muscle contraction can help to reduce blood loss following an injury (the vessel is said to be in “spasm”).

Question 20

What is an anastomosis?

Answer 20

Where arteries connect with each other without an intervening capillary network.

Question 21

What is the purpose of an anastomosis?

Answer 21

Provides alternative routes for blood to flow to supply the cells distal to an arterial occlusion (blockage)

Question 22

What is the Circle of Willis?

Answer 22

The arterial anastomosis of the brain.

Question 23

What does the Circle of Willis prevent?

Answer 23

a cerebrovascular accident (CVA/Stroke)

Question 24

What is a collateral?

Answer 24

Each alternative route in any given anastomosis

Question 25

What is an disadvantage of a collateral?

Answer 25

Bleed from both sides of a cut so the haemorrhage can be worse

Question 26

What is an end artery?

Answer 26

The ONLY arterial blood supply to a given area of the body

Question 27

What does infarction mean?

Answer 27

The irreversible cell death due to hypoxia (lack of oxygen) caused by loss of arterial blood supply

Question 28

What are the branches of the arch of aorta?

Answer 28

Brachiocephalic trunk, left common carotid artery andr right subclavian artery.

Question 29

What artery supplies the perineum?

Answer 29

internal iliac artery

Question 30

What artery supplies the lower limbs?

Answer 30

External iliac artery