Blood Vessels

Question 1

How many different types of capillaries are there?

Answer 1

3 types

Question 2

What are the three different types of capillaries?

Answer 2

Continuous

Fenestrated

Sinusoidal

Question 3

What is the most common type of capillary?

Answer 3

Continuous capillaries

Question 4

Write a note on continuous capillaries.

4

Answer 4

No pores

No gaps

Tight junctions between cells

Diffusion across the wall

Question 5

Name one place where continuous capillaries are found.

Answer 5

Gas exchange near alveoli

Question 6

Write a note on fenestrated capillaries.

4

Answer 6

Have pores than span the endothelial lining

Permit rapid diffusion of H2O, small peptides and such solutes

Present in the brain (choroid plexus - CSF), hypothalamus, pituitary gland and thyroid gland

Present in GIT absorptive surface and renal filtration sites

Question 7

Where are fenestrated capillaries found?

6

Answer 7

GIT absorptive surfaces

Renal filtration sites

Brain

Hypothalamus

Pituitary gland

Thyroid gland

Question 8

What is the main function of fenestrated capillaries?

Answer 8

They permit rapid diffusion of H2O

Question 9

Write a note on sinusoidal capillaries.

4

Answer 9

Large gaps in the endothelial cells

May have macrophages associated with them

Found in the liver

Have an absence of a basement membrane

Question 10

What are the three types of blood vessels?

Answer 10

Arteries

Capillaries

Veins

Question 11

What runs parallel to veins?

Answer 11

Lymph vessels

Question 12

How many different types of arteries are there?

Answer 12

Three

Question 13

What are the three different types of arteries?

Answer 13

Elastic arteries

Muscular arteries

Arterioles

Question 14

Write a note on elastic arteries.

3

Answer 14

Stretchy

Mostly wall is elastic and collagen (little muscle)

Also called windkessel vessels

Question 15

Give two examples of elastic arteries.

Answer 15

Aorta

Corotic artery in neck

Question 16

What are elastic arteries also called?

Answer 16

Windkessel vessels

Question 17

Describe the windkessel effect on the aorta.

5

Answer 17

It ensures smooth blood flow

The aorta is stretchy

The aorta fills as the heart pumps blood out

When the heart starts filling again the aorta recoils which pushes blood towards the arteriole

Blood leaves heart at a constant flow

Question 18

Define the windkessel effect.

Answer 18

A rhythmic fluid ejection from the heart is transformed into a fairly uniform flow in the arteries with reduced pressure oscillations (reduced pulse strength)

Question 19

What fibre type in the wall of the aorta allows the windkessel effect to happen?

Answer 19

Elastin fibres

Question 20

What happens to our elastic arteries as we get older?

2

Answer 20

As we get older we loose electricity

As this happens we lose compliance which is important in the heart and lung tissue

Question 21

What happens if our arteries loose their compliance?

Answer 21

It results in higher blood pressure

Question 22

Write a note on muscular arteries.

4

Answer 22

Three tunica

They are not completely open

Often called resistance vessels

They can change their radius

Question 23

What are muscular arteries also called?

Answer 23

Resistance vessels

Question 24

What does a change in the radius of a muscular artery determine?

Answer 24

Flow to any one area (often organs)

Hydrostatic pressure in capillaries

Question 25

What are the three tunica of a muscular artery?

Answer 25

Internal elastic lamina Tunica media Tunica externa

Question 26

What is the tunica media of muscular arteries?

Answer 26

A big thick muscular layer

Question 27

What is a tunica externa in a muscular artery?

Answer 27

A connective tissue layer

Question 28

What happens when you change the radius of a muscular artery? (2)

Answer 28

It determines blood pressure into capillaries It determines how much blood goes into any organ

Question 29

What is atherosclerosis?

Answer 29

Plaques of fat in vessels wall between intima and media lamina

Question 30

What is a stent? | 2

Answer 30

wire mesh put in an artery to keep it open A balloon catheter widens the artery and opens the mesh

Question 31

Write a note on arterioles. | 6

Answer 31

Resistance vessels Determine size of capillary exchange area Local factors control the number of capillaries receiving blood Thick muscular layer Branch off from muscular arteries Control where we send blood

Question 32

What do arterioles control?

Answer 32

Where we send blood

Question 33

What are veins also called?

Answer 33

Capacitance vessels

Question 34

What percentage of blood is in the veins?

Answer 34

64%

Question 35

What do all veins do?

Answer 35

They return blood to the heart They help us deal with a sudden loss of blood by acting as a reservoir

Question 36

What two organs are good stores of blood?

Answer 36

Liver and spleen

Question 37

How much of your blood can you loose before it becomes a medical emergency?

Answer 37

We can loose about 1/5th of our blood

Question 38

In relation to the heart what are veins called?

Answer 38

They are called the adjustable forechamber of the heart

Question 39

Why are veins called the adjustable forechamber of the heart?

Answer 39

They can decrease or increase flow back to the heart

Question 40

What percentage of blood volume is venous reserve?

Answer 40

About 20% of blood volume

Question 41

What veins have valves?

Answer 41

Veins in the limbs and the neck

Question 42

Why do veins have valves? | 2

Answer 42

To return the blood to the heart against gravity To compartmentalise blood (distribute its weight)

Question 43

What are varicose veins?

Answer 43

The valves in limbs don't work correctly

Question 44

How do veins differ from arteries?

Answer 44

Larger in diameter than arteries Have thinner walls than arteries Have lower blood pressure

Question 45

How many tunica do veins have?

Answer 45

Three tunica

Question 46

What three tunica do veins have?

Answer 46

Internal Tunica Media Tunica Externa

Question 47

What is the internal elastic media of veins made of?

Answer 47

Epithelia and connective tissue

Question 48

What is the tunica media of veins made of?

Answer 48

Smooth muscle and elastic

Question 49

What is the tunica externa of veins made of?

Answer 49

Connective tissue

Question 50

What are the three types of veins?

Answer 50

Venules Medium-sized veins Large veins

Question 51

What are venules? | 2

Answer 51

Very small veins Collect blood from capillaries

Question 52

What are medium-sized veins? | 2

Answer 52

Thin tunica media and few smooth muscle Tunica externa with longitudinal bundles of elastic fibres

Question 53

What are large veins? | 3

Answer 53

Veins with three tunica layers Thick tunica externa Thin tunica media

Question 54

What are venous valves ?

Answer 54

Folds of the tunica intima

Question 55

What do venous valves do?

Answer 55

They prevent blood from flowing backwards Compression - push blood towards the heart

Question 56

Where are large veins found?

Answer 56

In between skeletal muscle

Question 57

What happens when we exercise our skeletal muscle?

Answer 57

Our skeletal muscle works harder which forces blood up the veins harder

Question 58

Where do lymphatic vessels begin?

Answer 58

In the peripheral tissue

Question 59

Where do lymphatic vessels end?

Answer 59

They end by emptying into great veins

Question 60

What do lymphatic vessels do with their contents?

Answer 60

They return their fluid and solutes to general circulation

Question 61

What is the function of lymph vessels?

Answer 61

They transport fats from GIT to liver

Question 62

How do lymph vessels differ from veins?

Answer 62

Lymph vessels have more valves than veins

Question 63

What are shunt vessels?

Answer 63

Vessels joining arteries and veins, bypassing capillaries

Question 64

What is the function of shunt vessels?

Answer 64

They are important in thermoregulation