Physiology and Health Unit 2 KA 5

Question 1

What are the three types of Blood vessel?

Answer 1

1) Arteries
2) Capillaries
3) Veins

Question 2

Arteries divide up to form ____

(Fill in the blank)

Answer 2

Arteries divide up to form Capillaries

Question 3

Capillaries join up to make ____

(Fill in the blank)

Answer 3

Capillaries join up to make Veins

Question 4

What is the function of an Artery?

Answer 4

The function of an Artery is to carry blood away from the heart at high pressure

Question 5

What is the function of a Capillary?

Answer 5

The function of a Capillary is to allow the exchange of substances

Question 6

What is the function of a Vein?

Answer 6

The function of a Vein is to carry blood to the heart under low pressure

Question 7

Describe the wall structure of an Artery (3) -

Answer 7

• Thick outer wall
• Thick layer of muscle and elastic fibres
• Endothelium lining the narrow lumen

Question 8

Why do Arteries require strength and elasticity?

Answer 8

-Elastic walls are needed to withstand the surge of blood when the heart contracts.
-Smooth muscle is needed as it can contract for vasoconstriction/vasodilation

(blood vessels narrow/widen)

Question 9

What do Arteries carry?

Answer 9

Arteries carry oxygen and nutrients

Question 10

What does a pulse indicate?

Answer 10

A pulse indicates that blood is flowing through an Artery

Question 11

Describe the wall structure of Capillaries (2) -

Answer 11

• Very thin outer wall (1 cell thick)
• Very narrow lumen

Question 12

Why do Capillaries require thin walls?

Answer 12

Capillaries require thin walls so materials can be easily exchanged

(materials - gas, food, wastes)

Question 13

Capillaries form networks through organs/tissues, this gives them a large ____ ____

(Fill in the blank)

Answer 13

Surface area

Question 14

What leaves/enters Capillaries?

Answer 14

Oxygen leaves Capillaries
Carbon Dioxide enters Cappilaries

Question 15

Describe the wall structure of Veins (3) -

Answer 15

• Thin outer wall
• Thin layer of muscle and elastic fibres
• Endothelium lining the wide lumen
• contain valves

Question 16

What is the purpose of Valves inside Veins?

Answer 16

The purpose of valves is to prevent the backflow of blood

Question 17

What do Veins carry?

Answer 17

Veins carry Carbon dioxide and wastes

Question 18

Why do Veins need a wide lumen?

Answer 18

Veins need a wide lumen so there is less resistance to blood flow

Question 19

What is Blood pressure like in Arteries compared to Veins?

Answer 19

Blood pressure in the Arteries is higher than in the Veins

(as blood moves away from the heart, bp decreases)

Question 20

What does Vasoconstriction do to blood flow?

Answer 20

Vasoconstriction reduces blood flow as the smooth muscle contracts

Question 21

What does Vasodilation do to blood flow?

Answer 21

Vasodilation increases blood flow as the smooth muscle relaxes

Question 22

What does Blood consist of? (4)

Answer 22

1) Red blood cells
2) White blood cells
3) Platelets
4) Plasma

Question 23

What does Plasma contain that tissue fluid doesn’t?

Answer 23

Plasma contains plasma proteins and tissue fluid does not

Question 24

What happens when blood enters the Capillaries?

Answer 24

Blood enters the Capillaries by diffusion and undergoes pressure filtration

(Plasma proteins are too big to diffuse into tissue fluid)

Question 25

What does Tissue fluid supply cells with?

Answer 25

Tissue fluid supplies cells with glucose, oxygen and other substances

Question 26

What happens to most of the Tissue fluid?

Answer 26

Most of the tissue fluid returns to the blood in the capillaries

Question 27

How is excess Tissue fluid absorbed?

Answer 27

Excess tissue fluid is absorbed by thin-walled lympathic vessels, the fluid is now called lymph