All insects possess a rigid exoskeleton with a waxy coating that is impermeable to gases
What is a spiracle
A spiracle is an opening in the exoskeleton of an insect which has valves
It allows air to enter the insect and flow into the system of tracheae
What is a tracheae?
Tracheae are tubes within the insect respiratory system which lead to tracheoles (narrower tubes)
What keeps the Tracheae open?
Ridgid rings of Chitin
Label the diagram
A) Spiracle
B) Exoskeleton
C) Trechea
D) Air sac
E) Tracheoles
Very active, flying insects need a more rapid supply/intake of oxygen. They create a mass flow of air into the tracheal system by:
Closing the spiracles
Using abdominal muscles to create a pumping movement for ventilation
Also, during flight the fluid found at the narrow ends of the tracheoles is drawn into the respiring muscle so gas diffuses across quicker (due to the diffusion distance being shorter)
