RESPIRATION question answer

 

Q.1: Define the term respiration.

Ans:-RESPIRATION

The term respiration in applied to the process of breathing, namely

inhaling and exhaling and the mechanism of exchange of gases oxygen

and carbon dioxide.

More precisely respiration means series of chemical reactions by which

the living cell obtain energy for its various life functions from different types

of food. It is because most of the organisms need oxygen to produce energy

from glucose in the form of ATP.

Aquatic animals obtain oxygen dissolved in water while land animals

obtain from the air that surrounds them.

Q.2: Describe Respiration in Hydra, Planarian and Earthworm.

Ans:-RESPIRATION IN HYDRA

Hydra has no specialized system for respiration. The exchange of gases

takes place through the whole surface of the body where ever it is in contact

with the water. The cells of inner layer obtain oxygen and release carbon

dioxide in water within the digestive cavity while cells of outer layer of body

make gaseous exchange with surrounding water. Thus respiration occurs by

simple diffusion.

RESPIRATION IN PLANARIAN

The gaseous exchange in planarian is carried out over the whole

surface of the body, by simple diffusion, which is in direct contact with water.

Planarian is a free-living animal and is quite active. So it requires a continued

supply of oxygen. Its external surface is large in relation to the size of the

body, the required amount of oxygen is easily obtained.

 

RESPIRATION IN EARTH WORM

 

Earthworm has no special respiratory organs. The exchange of gases

takes place mainly through the skin which is richly supplied by blood

capillaries. The skin is always Kept moist by the secretion of the epidermal

mucous gland cells and also by the coelomic fluid passing out through the

dorsal pores. Oxygen in solution diffuses through the cuticle. epidermis and

walls of capillaries into the blood where it combines with the hemoglobin to

form oxyhemoglobin. The blood now moves around the body. carrying oxygen

to all the tissues and cells where blood gives up the oxygen.

 

The blood does net come into direct contact with the tissue cells so

that oxygen must be handed over through the tissue fluids. coelomic fluids.

etc. Similarly carbon dioxide is removed from the tissues by the blood and

carried in solution in the plasma to the skin, from where it diffuses out.

                            A digrammatic sketch of breathing mechanism in grasshopper

 

Q.3: Describe Respiration in Grasshopper.

Respiration in Grasshopper

Grasshopper has a branching system of air tubes called tracheae for

the exchange of gases. The main tracheal trunks (tubes) open to the exterior

by paired openings called spiracles present on the sides of the body. There

are ten pairs of spiracles, two in the thorax and one pair in each of the first

eight abdominal segments. The main tracheae divide and subdivide finally

forming very fine tubes called tracheoles. These tracheoles form a sort of end

cell which is partly filled with fluid. Oxygen dissolves in this fluid. These

tracheoles surround the organs and tissues and continuously supply oxygen to

the living cells directly by diffusion. Due to concentration gradient oxygen

enters the spiracles, passes, through the tracheal tubes and reaches the body

cells. The contraction of expansion of the abdomen facilitates the movement

of air through the tracheal trunks.