Exchange And Transport Systems: - Gas Exchange In Insects

- Gas Exchange in insects -

Insects do not have a transport system so gases would need to transported directly into the respiring tissues. 

Insects use tracheae to exchange gases 

Insects have microscopic air-filled pipes = Tracheae

The air moves into the tracheae through the pores on the surface = Spiracles 

On the insect there are spiracles which are placed along side the body // These spiracles are openings of small tubes running into the insects body. 

Oxygen moves down a concentration gradient towards the cells.

The tracheae branches off into tracheoles //
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Adaptations =
- Thin = quicker rate of diffusion
- Permeable walls = diffusion occurs down a gradient (active transport not needed to pass the molecules)
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Oxygen diffuses into the respiring cells.

Water at the end of the tracheoles allows for a concentration gradient to be maintained // the

Carbon dioxide from the respiring diffuse into the water (higher concentration of CO2 // lower concentration of 02 in the respiring cells).

Rhythmic abdominal movement = moves the air in and out of the spiracles.