Extra Gas Exchange

Question 1

Why cant large organisms do gas exchange by diffusion?

Answer 1

As an organisms size increases, surface area to vol ration decreases, so diffusion across surface not efficient enough

Question 2

Describe the adaptations of an amoeba

Answer 2

Single celled so large surface area and thin

Question 3

Describe the adaptations of a flatworm for gas exchange

Answer 3

Flat so thin and short diffusion pathway

Question 4

Describe the adaptations of an earthworm for gas exchange

Answer 4

Skin secretes mucus so moist, slow moving so low metabolic rate, blood vessels maintain diffusion gradient

Question 5

Describe amphibians gas exchange surfaces.

Answer 5

Skin main respiratory surface and is moist and permeable. Capillary network maintains diffusion gradient. When active lungs used

Question 6

Describe the gas exchange surface of reptiles.

Answer 6

Use lungs which have a large surface area

Question 7

What do birds use for gas exchange?

Answer 7

Air sacs

Question 8

Describe the gill structure

Answer 8

Gill arch (bone), with gill filaments which have gill plates, gill rakers