WAEC - Biology (1997 - No. 10)
Which of the following structures is associated with respiration in insects?
Air sac
Spiracle
Lung
Alveolus
Gill
Selitys
The body of the insect is covered with holes called spiracles. The oxygen enters these holes and reaches the trachea which helps them to circulate throughout the body. The carbon dioxide is carried by the trachea and expelled out through the spiracles.