Question

(a) What is the significance of the presence of mucus and hair in nasal cavity?
(b) Why don't trachea or windpipe doesn't collapse when there is no air inside?
(c) Define aerobic and anaerobic respiration?

Answer 1

(a) The hairs present in nasal passage trap the dust particles present in the inhaled air thus allowing only the filtered air to enter into the body. Mucus moistens the air and traps dust particles.
(b) The trachea is supported by the series of the cartilaginous rings which are c-shaped. These rings prevent the trachea from collapsing.
(c) Aerobic respiration is the respiration where glucose is broken down by oxygen to release energy along with carbon dioxide and water being produced as by-products of the reaction.

Anaerobic respiration is the respiration which occurs in the absence of oxygen to produce the energy.