KA5 Structure & Function of Artries, capillarys, Veins

Question 1

What is the function of an artery

Answer 1

Carry blood away from heart at high pressure

Question 2

what is the wall structure of an artery

Answer 2

• thick outer layer containing elastic fibres
• middle layer of smooth muscle & elastic fibres
• lining of endothelium

Question 3

what size is the lumen in an artery

Answer 3

Narrow

Question 4

What is function of the thick and elastic wall in the artery

Answer 4

withstands surge of blood when heart contracts

Question 5

What is the function of Smooth muscle in artery walls

Answer 5

Controls blood flow by contracting and relaxing causing vasoconstriction, vasodilation

Question 6

What is the function of a capillary

Answer 6

Allows exchange of substances

Question 7

what is the wall structure of a capillary

Answer 7

very thin, one cell thick

Question 8

what size is the lumen in a capillary

Answer 8

very narrow

Question 9

what is the function of a vein

Answer 9

carries blood towards the heart

Question 10

what is the wall structure of a vein

Answer 10

• thin outer layer containing elastic fibres
  *middle layer containing muscle and elastic fibres
• lining of endothelium

Question 11

What size is the lumen in a vein

Answer 11

wide

Question 12

what is the function of a wide lumen in a vein

Answer 12

less resistance to blood flow

Question 13

What does blood consist of

Answer 13

red blood cells, white blood cells, platelets and plasma

Question 14

what is plasma

Answer 14

watery yellow fluid that contains all blood cells and glucose, amino acids, carbon dioxide, plasma proteins & ions

Question 15

why is blood forced into capillaries

Answer 15

blood arriving at ateriole side of capillary bed at a higher pressure thus it undergoes pressure filtration

Question 16

what does pressure filtration do

Answer 16

causes much of plasma to pass through thin capillary walls into tissue fluid surrounding the cell

Question 17

why cant plasma proteins be filtered through capillary walls

Answer 17

too large

Question 18

what does tissue fluid supply cells with

Answer 18

Glucose and Oxygen

Question 19

what does into tissue fluid from cells

Answer 19

Cardon dioxide and Urea

Question 20

where does tissue fluid go

Answer 20

back into blood through capillaries at venule side of capillary bed

Question 21

where does excess fluid go

Answer 21

absorbed by thin-walled lymphatic vessels, fluid is now called lymph and returns lymph to circulatory system (bs)