Respiratory Systems | MCQs

Explanation

Instead of nostrils, insects breathe through openings in the thorax and abdomen called spiracles.

Insects that are diapausing or non-mobile have low metabolic rates and need to take in less oxygen.

Insects exchange oxygen and carbon dioxide through spiracles (noted by circle)

Explanation

Bronchial respiration refers to respiration through gills, mainly seen in fishes.

Gills extract dissolved oxygen from water and expel carbon dioxide.

Explanation

The lungs are the primary organs for gas exchange, where oxygen is absorbed into the blood, and carbon dioxide is expelled.

This process occurs in the alveoli, tiny air sacs in the lungs.

Explanation

The main reason for adding helium to the breathing mixture is to make the nitrogen-oxygen ratio lower than the air ratio so that the gas mixture can breathe safely in the deep sea. Lower levels of nitrogen are needed to reduce deep gas nitrogen anesthesia and other physiological effects.

Explanation

Aquatic arthropods like crabs, prawns, and some aquatic insects use gills to extract oxygen from water.

Gills provide a large surface area for gas exchange in an aquatic environment.