Question

Give an account on the tracheal system of a cockroach.

Answer 1

Hint: Cockroach is a terrestrial organism as well as omnivorous insect under phylum Arthropoda. In cockroaches, the trachea plays a prominent role in exchange for gases and has a network of air tubes for respiration purposes. Oxygen is absorbed passively through the moist skin and it feeds on food grains and even other animals.

Complete step-by-step answer:

1. The Trachea system is generally the airway present in cockroaches that leads from the larynx (which is also called the voice box) to the bronchi which extend into the lungs.
2. This is a network system that functions as a respiratory organ that helps in supplying oxygen to several target organs. Cockroaches do not have lungs. So, instead, they have a network of tubes called the tracheal system.
3. There are ten pairs of spiracles that are present on the lateral side of the body of the cockroach. Each spiracle’s shape is oval and also has a filtering apparatus that helps in eliminating dust particles coming from the inflowing air.
4. Trachea opens up at the surface of the thorax and abdomen through paired valve-like structures called spiracles.
5. Muscles surrounding spiracles are closed most of the time but are allowed to open only when oxygen needs to be taken and release carbon dioxide as a waste from the body.
6. Exchange of oxygen and carbon dioxide happen in tissues happens by a diffusion process through the thin walls of tracheoles.

Respiration of cockroaches consists of two phases:
(a) Inspiration: Involves intake of oxygen into the tracheal system. It is a passive process.
(b)Expiration: This involves the elimination of carbon dioxide. It is an active process.

Note:Person should be aware of the respiratory system of mammals to relate to the tracheal system of cockroaches. With this, should also have knowledge regarding the classification of mammals.