Exchange Systems

Question 1

How do single felled organisms exchange substances with the environment

Answer 1

Substances and diffuse directly into and out of the cells across the cell surface membrane
This is at a fast rate because of the short diffusion distance

Question 2

How do multicellular organisms exchange substances with the environment

Answer 2

Specialised exchange organs
Mass transport

Question 3

Why can’t multicellular organisms exchange substances with the environment via simple diffusion

Answer 3

Because it is too slow
Since some cells are deep within the body ( which is too large of a distance)
Since larger animals have a larger surface area to volume ratio

Question 4

What three factors does heat exchange depend on

Answer 4

Body size ( dependant on the surface area , meaning the larger the surface area to volume ratio , the more heat is lost)
Body shape ( dependant on the compactness of the animal depends on heat loss , the more compact the less heat lost)
Adaptations for heat exchange ( have the animals body has changed to suit the environment)

Question 5

Give some behavioural adaptations to aid exchange

Answer 5

Small animals in cold regions eat high energy foods to support high metabolic function

Question 6

Mane some physiological adaptations to aid gas exchange

Answer 6

Animals with high surface area to volume ration in hot climates , lose lots of water via sweat, therefore they have adapted there kidney structure to produce less urine and to prevent less water loss.