Write a brief note on tracheal respiration in insects .

Explanation

(1)In insects blood has no haemoglobin and is white in colour. Hence it cannot carry oxygen .
(2)For respiration insects adopt a special system called tracheal system
(3)This system consists of a series of tubes called trachea .
(4)These trachea open out through small apertures called spiracles on either side of the body .
(5)All tracheal tubes of each side join and form a longitudinal tracheal trunk.
(6)Trachea divide into a number of brances called tracheoles which carry air directly to the tissues.
(7)As the air moves in and out of the trachea , oxygen present in the air diffuses into the cells and `CO_2` diffuses into the air from the cells.