Structure Of Arteries

Question 1

What is the central space of a blood vessel called and what is it lined with ?

Answer 1

• lumen

* limed with endometrium

Question 2

What do the arteries do

Answer 2

Carry blood at high pressure AWAY from the heart

Question 3

What are the smallest arteries called and what do they do?

Answer 3

Arterioles

Supply blood to capillaries

Question 4

Structure of artery

Answer 4

Central layer - lumen
Middle layer - smooth muscle with elastic fibres
Outer layer- elastic wall

Question 5

What causes high pressure blood into arteries ?

Answer 5

Contractions of the heart

Question 6

What do the elastic fibres in arteries do? (2)

Answer 6

Allow artery walls to stretch as blood passes through

Fibres recoil between beats to maintain high pressure

Question 7

What is it called when the smooth muscle contracts to decrease diameter of lumen

Answer 7

Vasoconstriction

Question 8

What does vasoconstriction do?

Answer 8

Decreases the flow of blood to capillaries

Question 9

What happens when smooth muscle is relaxed

Answer 9

Vasodilation

Question 10

What is vasodilation

Answer 10

Increases blood flow to capillaries

Question 11

What do veins do?

Answer 11

Carry Low blood pressure back to the heart

Question 12

What are the smallest veins called?

Answer 12

Venules

Question 13

What do venules do?

Answer 13

Remove blood from the capillaries

Question 14

Structure of a vein

Answer 14

• elastic outer layer
• thin muscular wall
• wise lumen - and endometrium
• valves

Question 15

What do valves do

Answer 15

Prevent backflow of blood to heart at low pressure

Question 16

What do capillaries do

Answer 16

Exchange substances carried in blood

Question 17

Structure of capillaries & what does it allow

Answer 17

Have lumen and very thin walls and endothelium

Quick exchange of materials

Question 18

Where do capillaries occur and where are they

Answer 18

Occur in capillary beds which run between body tissue

Question 19

What does high pressure of arteriolar blood cause

Answer 19

Pressure filtration which causes capillaries to exclude plasma

Question 20

What does plasma become?

Answer 20

Tissue fluid which bathes in cells

Question 21

What does tissue fluid do?

Answer 21

Exchanges materials with cell and returns to capillaries by osmosis and diffusion

Question 22

What happens to excess tissue fluid

Answer 22

Drains into lymph vessels and become lymph

Question 23

What is the pressure of lymph fluid

Answer 23

Even lower than that of blood in veins

Question 24

What does lymph vessels contain

Answer 24

Valves
Lymph nodes
Lymph capillaries

Question 25

What do skeletal muscles do

Answer 25

Squeeze lymph through valves

Question 26

What does the lymphatic system do

Answer 26

Returns lymph fluid back to blood stream

Question 27

Where does returning lymph go

Answer 27

Passes through series of lymph nodes

Question 28

What do lymph nodes contain

Answer 28

Lymphocytes and other immune cells

Question 29

What do lymph nodes do?

Answer 29

Act as a filter- removing foreign particles from lymph fluid