Anatomy of the Cardiovascular System 2

Question 1

What are the layers of a blood vessel?

Answer 1

Tunica intima
Tunica media
Tunica adventitia

Question 2

What is the basic structure of the tunica intima?

Answer 2

Simple squamous epithelium
Basement membrane
Connective tissue

Question 3

What is the basic structure of the tunica media?

Answer 3

Smooth muscle tissue

Elastic tissue

Question 4

What is the basic structure of the tunica adventitia?

Answer 4

Fibrous connective tissue

Question 5

What in the most outer layer of a blood vessel?

Answer 5

Tunica adventitia

Question 6

What is the difference between an artery and its accompanying vein?

Answer 6

Arteries are generally smaller in diameter and will have a thicker wall than their accompanying vein
Arteries have a thick media and thin adventitia
Veins have a thin media and a thick adventitia

Question 7

What are the different types of arteries?

Answer 7

Elastic
Muscular
Arterioles

Question 8

What is the only elastic artery?

Answer 8

The aorta

Question 9

What is the function of the aorta?

Answer 9

Pressure reservoir

Question 10

What happens to the aorta during diastole?

Answer 10

Heart relaxes, pressure falls and the artery recoils so that pressure is maintained on the blood

Question 11

What is the recoil and stretchability of the aorta due to?

Answer 11

Presence of extensive amounts of elastic fibres in the tunica media in the form of laminae, these fibres are secreted by smooth muscle

Question 12

What is the function of the muscular arteries?

Answer 12

Controls distribution of blood to regions

Question 13

In muscular arteries, elastic fibres are concentrated in two well-defined sheets, what are these?

Answer 13

Internal elastic lamina (just under the epithelium)

External/outer elastic lamina (between tunica media and adventitia)

Question 14

Smaller muscular arteries gradually change histologically to become what?

Answer 14

Arterioles

Question 15

What is the difference between the layers of muscular arteries and arterioles?

Answer 15

Arterioles do not have a tunica adventitia

Question 16

What is the function of the arterioles?

Answer 16

Controls blood flow to the capillary beds and controls blood pressure

Question 17

What is the function of capillaries?

Answer 17

Main exchange site for nutrients and gases

Question 18

What are pericytes and what is their function?

Answer 18

Pericytes are an incomplete layer of cells surrounding the basement membrane which have contractile properties and help to control flow of blood in the capillarie

Question 19

Is the blood pressure in capillaries high or low?

Answer 19

Low

Question 20

What extra property do continuous capillaries have?

Answer 20

Can control what is exchanged

Question 21

How is material passed through continuous capillaries?

Answer 21

Must pass through the cell or between the cells via selective transport mechanisms

Question 22

What extra property do fenestrated capillaries have?

Answer 22

Have fenestrations (pores) of up to 100µm

Question 23

What is the function of diaphragms in fenestrated capillaries?

Answer 23

Filter molecules by molecular weight and/or charge

Question 24

What is the difference between continuous and discontinuous capillaries?
What does the structure of discontinuous capillaries allow?

Answer 24

Discontinuous capillaries have gaps between the endothelial cells and basement membrane
Allows free passage of fluid and cells

Question 25

What has a larger diameter; sinusoids or discontinuous capillaries?

Answer 25

Sinusoids

Question 26

Where are sinusoids found?

Answer 26

Where large amounts of exchanges take place e.g. liver

Question 27

What does the tunica intima of sinusoids contain?

Answer 27

Phagocytic cells

Question 28

What is the function of valves in veins?

Answer 28

Prevent the back flow of blood

Question 29

What are the main differences between superficial and deep veins?

Answer 29

Superficial veins are thick walled and have no surrounding support Deep veins are thin walled and have surrounding support from deep fascia and muscles

Question 30

What does the lymphatic system drain into?

Answer 30

Systemic venous system

Question 31

Where are lymph nodes found?

Answer 31

Alongside major veins and around origins of major arteries

Question 32

How are lymph nodes clinically important?

Answer 32

In tumour cell metastases

Question 33

What are the features of lymph capillaries?

Answer 33

Blind-ended capillaries lined by very thin endothelium No fenestrations Absent/rudimentary basal lamina Anchoring filaments linking endothelial cells to surrounding tissue No RBCs in lumen

Question 34

What is the nerve supply of blood vessels?

Answer 34

Sympathetic, or sympathetic and parasympathetic