Structure and function of blood vessels

Question 1

State the oxygenated blood flow from the heart (left side) through the blood vessels in systemic circulation

Answer 1

heart
↓
aorta
↓
arteries
↓
arterioles
↓
capillaries

Question 2

State the deoxygenated blood flow to the heart (right side) through the blood vessels in the pulmonary circulation

Answer 2

capillaries
↓
venules
↓
veins
↓
vena cava
↓
heart

Question 3

State the blood flow to the lungs

Answer 3

heart
↓
pulmonary artery
↓
lungs

Question 4

State the blood flow from the lungs

Answer 4

lungs
↓
pulmonary veins
↓
heart

Question 5

What is the outermost layer in blood vessels?

Answer 5

tunica adventitia / externa

Question 6

What is the structure of the tunica adventitia?

Answer 6

connective tissue - collagen, elastin
(withstand high blood pressure)

Question 7

What is the middle layer in blood vessels?

Answer 7

tunica media

Question 8

What is the structure of the tunica media?

Answer 8

• smooth muscle (contractile for blood flow)
• elastin (connective)

Question 9

What is the innermost layer in blood vessels?

Answer 9

tunica intima

Question 10

What is the structure of the tunica intima?

Answer 10

endothelial cells

Question 11

What blood vessels are connected to the left side of the heart?

Answer 11

elastic artery
muscular artery
arteriole
continuous capillary

Question 12

What blood vessels are connected to the right side of the heart?

Answer 12

large vein
medium sized vein
venule
fenestrated capillary

Question 13

Define elasticity

Answer 13

ability to absorb & smooth pressure pulses during the cardiac cycle

Question 14

Define contractility

Answer 14

ability to change diameter of blood vessel & blood flow

Question 15

What are the 2 structural types of arteries?

Answer 15

• elastic
• muscular

Question 16

Describe the elastic artery

Answer 16

conducting vessels (transports blood to body) that absorbs pressure
- e.g aorta, pulmonary artery

Question 17

Describe the muscular artery

Answer 17

distribution vessels that are contractile to change blood flow for different tissues
- e.g femoral artery

Question 18

What is antheroscelrosis (condition)?

Answer 18

• deposits of lipid, Ca & collagen (plaque)
• makes blood vessels more rigid

Question 19

What is arterial stiffness?

Answer 19

rigidity of blood vessel

Question 20

What do pulsatility waveforms indicate?

Answer 20

arterial stiffness, workload on heart, risk of cardiovascular disease

Question 21

What does pulsatility waveforms indicate?

Answer 21

• arterial stiffness
• workload on heart
• risk of cardiovascular disease

Question 22

What are arterial aneurysms?

Answer 22

weaknesses in blood vessels

Question 23

Describe the structure of arterioles

Answer 23

• rings of smooth muscle cells
• endothelium layer
• capillaries branching of

Question 24

What is the function of smooth muscle cells in arterioles?

Answer 24

regulates blood flow by vasoconstriction & vasodilation

Question 25

State the 3 types of capillaries in order of increasing permeability

Answer 25

continuous
fenestrated
sinusoidal

Question 26

What is the function of capillaries?

Answer 26

site of exchange between blood & cells

Question 27

What is the diffusion rate (in capillaries) dependent on?

Answer 27

• diffusion distance
• conc gradient
• SA
• molecule size

Question 28

What are the routes of diffusion in capillaries?

Answer 28

• between cells
• through fenestrations
• across cell wall (mechanism)

Question 29

What is Pi?

Answer 29

interstitial hydrostatic pressure

Question 30

Pc

Answer 30

Capillary hydrostatic pressure

Question 31

πi

Answer 31

Interstitial colloid osmotic pressure

Question 32

πc

Answer 32

Capillary colloid osmotic pressure

Question 33

Jv

Answer 33

net fluid movement across capillary wall

Question 34

hydrostatic pressure across capillary

Answer 34

Pi into capillary
Pc out of capillary

Question 35

What is the colloid osmotic pressure across the capillary?

Answer 35

πc into capillary
πi out of capillary

Question 36

What is a haemorrhage?

Answer 36

• reduction in blood V & blood P
• Pc decreases so Jv decreases
• increased reabsorption from interstitial fluid to plasma
• compensatory recall of fluids

Question 37

dehydration

Answer 37

• reduction in plasma volume & increased plasma protein concentration
• decreased Pc & increased πc leads to decreased Jv
• increased reabsorption from interstitial fluid to plasma
• compensatory recall of fluids

Question 38

What is an oedema?

Answer 38

Excess fluid in the tissues of the body
- high Pc / low πc
- due to: hypertension, heart failure, low plasma protein concentration, severe burns, blockage of the lymphatic vessels

Question 39

What can oedema cause?

Answer 39

cause fluid accumulation in interstitial fluid (fluid surrounding cells in tissues)

Question 40

What are the causes of oedema?

Answer 40

hypertension
- heart failure
- low plasma protein conc
- severe burns
- blockage of lymphatic vessels

Question 41

What is pulmonary oedema?

Answer 41

fluid accumulation in pulmonary interstitium & air spaces

Question 42

What is the pulmonary oedema caused by?

Answer 42

• left ventricle failure
• pulmonary hypertension

Question 43

What does pulmonary oedema lead to?

Answer 43

hypoxaemia
hypercapnia

Question 44

What are the functions of veins & venules?

Answer 44

delivers deoxygenated blood back to heart