Chapter 7 (Exchange Surfaces and Breathing)

Question 1

Where does air enter insects through?

Answer 1

Spiracles

Question 2

What is tracheal fluid?

Answer 2

Found at the ends of tracheoles in insects. Limits the penetration of air by diffusion. Removed when oxygen demand is high, causing lactic acid build up in cells which pulls water out of the tracheoles by osmosis.