module 3 exchange and transport (booklet 2)

Question 1

small simple organisms

Answer 1

-rely on simple diffusion
-large SA:VOL
-short diffusion distances
-unicellular
-low metabolic rate

Question 2

multicellular organisms

Answer 2

eg. fish, insects reptiles and mammals
-more cells - higher metabolic rate
-smaller SA:VOL
require specialised transport system

Question 3

large multicellular organisms need a transport system to

Answer 3

-supply all cells with oxygen and glucose p
-remove metabolic waste (co2, urea)

Question 4

endotherms

Answer 4

warm blooded (birds and mammals)

Question 5

ectotherms

Answer 5

cold blooded (reptiles, amphibians, fish)

Question 6

circulating fluid

Answer 6

blood in most organisms, haemolymph in insects.

Question 7

what is the purpose of circulating fluid

Answer 7

• used to carry o2 and glucose, hormones, urea
  -o2 is often carried in erythrocytes by haemoglobin

Question 8

pumping device

Answer 8

heart
-creates pressure difference between 2 different areas which allows blood flow

Question 9

blood vessels

Answer 9

partially in most organisms to carry blood towards the tissues and back to the heart

Question 10

valves

Answer 10

prevent back flow of blood and ensure a unidirectional flow

Question 11

input from an exchange surface

Answer 11

enables substances , eg o2 & co2 to enter and leave the blood

Question 12

circuits

Answer 12

can have 2,
1-pick up o2
1-to deliver o2