RESPIRATORY ORGAN:
The respiratory organ in cockroach is called trachea which is a network of tubes.
STRUCTURE:
Trachea opens to outside by ten (10) pairs of breathing pores called spiracles. Spiracles are present on the lateral side of the body of cockroach. Two (2) pairs of spiracles are present in the region of thorax while eight (8) pairs are present in abdomen. Valves control the opening and closing of spiracles.
MECHANISM OF RESPIRATION:
The trachea is further divided into small and fine branches which are called tracheoles. The ends of tracheoles are filled with a fluid so that the oxygen entering the tracheoles dissolve in it.
The tracheoles then enter the a tissue. The exchange of respiratory gases takes place between tracheoles and the cells by diffusion. The respiratory movements of abdomen pumps the air in and out of the spiracles.
