Cardiovascular System

Question 1

What does the cardiovascular system do?

Answer 1

Circulate and transport nutrients, oxygen, carbon dioxide, hormones and blood cells to and from the cells of the body
Fights disease, stabilises temperature, ph and helps maintain homeostasis

Question 2

What are the three essential components of the cardiovascular system?

Answer 2

Heart, blood and blood vessels

Question 3

What is the pulmonary circulation?

Answer 3

a loop through the lungs where blood is oxygenated

Question 4

What is the systemic circulation?

Answer 4

a loop through the rest of the body to provide oxygenated blood and receive deoxygenated blood

Question 5

What is a closed circulatory system?

Answer 5

Blood never leaves the vessels

Question 6

How much blood does an average adult have?

Answer 6

5 litres

Question 7

How many litres of blood is red blood cells and plasma?

Answer 7

Red blood cells- 2 litres

Plasma- 3 litres

Question 8

Where is most of your blood at any given time?

Answer 8

Veins

Question 9

What is bridging?

Answer 9

compression of a segment of coronary artery during systole, causing narrowing that reverses during diastole

Question 10

What is an end artery?

Answer 10

Terminal artery supplying all or most of the blood to a body part without significant collateral circulation
e.g. coronary artery, splenic artery, cerebral arteries and renal arteries and absolute- retina

Question 11

What is collateral circulation?

Answer 11

branches of artery are used to supply blood

Question 12

What occurs in systole?

Answer 12

Left ventricle contraction causes the blood pressure in the aorta to rise and the walls if the elastic arts stretch

Question 13

What occurs in diastole?

Answer 13

Aortic semi-lunar valves close, and the walls of the aorta recoil, maintaining pressure in the blood and moving it towards the heart and smaller vessels, aortic pressure drops

Question 14

What do elastic arteries act as?

Answer 14

pressure reservoirs

Question 15

What are the three layers of an artery and vein wall?

Answer 15

Tunica intima (inside), tunica media, tunica adventitia (outside)

Question 16

What is an Aneurysm?

Answer 16

A dilation of a blood vessel

Question 17

What is the tunica intima made out of?

Answer 17

Endothelium

Question 18

What is the tunica media made out of?

Answer 18

Smooth muscle

Question 19

What s the Tunica adventitia made out of?

Answer 19

Fibroelastin connective tissue

Question 20

What are arterioles?

Answer 20

Arteries with a diameter of less than 0.1mm

Question 21

What are Metarterioles?

Answer 21

Artie that supply blood to capillary beds

Question 22

What is a precapillary sphincter?

Answer 22

Allow the articles and metarterioles to serve as flow regulators for the capillary bed

Question 23

If precapillary sphincters are open what occurs?

Answer 23

plentiful blood flow through the capillary bed

Question 24

What occurs to arterioles during exercise?

Answer 24

Blood flow to skeletal muscle is increased by dilation of arterioles and blood flow to intestine is decreased by constriction of arterioles

Question 25

How much of our total blood volume do capillaries hold?

Answer 25

5%

Question 26

What happens in capillaries?

Answer 26

Gas and nutrient exchange

Question 27

What is a capillary made from?

Answer 27

single layer of endothelium and basement membrane

Question 28

What is a pericyte?

Answer 28

Form a branching network on the outer surface of the endothelium, can differentiate into muscle cells and fibroblasts

Question 29

What is a post capillary venule?

Answer 29

receive blood from capillary- more permeable, fluid drains into them due to low pressure

Question 30

What is a valve?

Answer 30

A venule made of thin extensions

Question 31

What are the characteristics of a vein?

Answer 31

large diameter, thin wall, more connective tissue, fewer elastic and muscle fibres

Question 32

What is capacitance?

Answer 32

Ability of blood vessel to increase the volume of blood it holds without a large increase in pressure

Question 33

How does blood get from the legs to the heart?

Answer 33

muscle contraction, thoracic pump causes negative pressure when breath in and out from diaphragm, valve prevents backflow

Question 34

What does calf muscle pump failure lead to?

Answer 34

Venous hypertension

Question 35

What does gravity cause for the body?

Answer 35

vertical gradient of Venous pressure