Respiration In Plants And Animals

Question 1 Describe the process of respiration in leaves of a plants?

Question 2 Describe the process of respiration in the roots of a plant?

Question 3 Describe the process of respiration in Earthworm?

Question 4 Describe the process of respiration in Fish?

Question 5 Describe the process of respiration in Insects?

Question 6 Name the breathing organs in Fish, Earthworm, Frog and insects?

Some of the animals which do not have lungs for breathing are earthworm, fish, cockroach, grasshopper, mosquitoes, houseflies and ants.

Breathing in Earthworm

1) The earthworm breathes through its skin.

2) The skin of earthworm is quite thin and moist.

3) Gases can easily pass through the skin of earthworm. The skin of earthworm has a good blood supply.

 

4) The earthworm absorbs the oxygen (of air) needed for respiration through its thin and moist skin. This oxygen is then transported to all the cells of the earthworm by its blood where it is used in respiration (production of energy).

5) The carbon dioxide produced during respiration is carried back by the blood. This carbon dioxide is expelled from the body of the earthworm through its skin.

Frog is an animal which can breathe through lungs as well as its moist skin.

Breathing in Fish

1) The animals living under water have gills for breathing.

2) Gills are projections of the skin. Gills have blood vessels for the exchange of respiratory gases (oxygen and carbon dioxide).

3) The gills help the fish to use oxygen which is dissolved in water. The fish has gills on both the sides of its head.

4) The gills are covered by gill covers so they are not visible from outside. The fish breathes by taking in water through its mouth and sending it over the gills.

5) When water passes over the gills, the gills extract dissolved oxygen from this water. The extracted oxygen is absorbed by the blood and carried to all the parts of the fish for respiration (release of energy).

6) The carbon dioxide produced during respiration is brought back by the blood into the gills for expelling into the surrounding water. 

7) Some other aquatic animals like prawn, crab and fresh water mussel also respire through gills or similar structures.

8) Some sea-animals like dolphins and whales which live in water but do not have gills. Dolphins and whales breathe in air through their nostrils (called blowholes) which are located on the upper parts of their heads. Dolphins and whales come to the surface of sea-water from time to time to breathe in air. We (human beings) cannot survive under water because we have no gills to make use of oxygen dissolved in water for breathing.

 

Breathing in Insects

1) All the insects have tiny holes on the sides of their body which are called spiracles.

2) The spiracles on the body of insects are connected to a network of thin air-tubes called tracheae which spread into the whole body of the insect.

3) Air (rich in oxygen) enters into the insect through spiracles by the up and down movements of its body. This air goes into the network of thin air-tubes called tracheae.

4) From the tracheae, oxygen of air diffuses into the body tissues of insect and reaches each and every cell of its body where it is utilised in respiration (production of energy).

5) Carbon dioxide produced during respiration in the cells diffuses into tracheae and carried to the spiracles where it is expelled in the process of breathing.

6) For example: Cockroach has spiracles (tiny holes) on the sides of its body and tracheae (air-tubes) throughout inside its body for the process of breathing and respiration.

7) The insects such as grasshoppers, mosquitoes, houseflies, bees and wasps also have spiracles and tracheae for breathing and respiration.

8) Insects have blood in their body but it is not red because it does not contain haemoglobin. Since the blood of insects does not contain haemoglobin, so it cannot carry oxygen to all the parts of the body. Every part of the body of an insect gets oxygen through a network of big and small air tubes.

Respiration In Plants

1) The plants get energy by the process of respiration in which glucose food (prepared by them) breaks down in the presence of oxygen (of air) to form carbon dioxide and water with the release of energy.

2) Plants take oxygen from air for respiration and give out carbon dioxide. So, just like animals, respiration in plants also involves the exchange of gases: oxygen and carbon dioxide.

In plants each part can independently take in oxygen from air, utilise it to obtain energy, and give out carbon dioxide. 

Respiration in Leaves

The leaves of plants have tiny pores on their surface which are called stomata. The exchange of gases (oxygen and carbon dioxide) in the leaves during respiration takes place through stomata.

Oxygen from air enters into a leaf through stomata and reaches all the cells by the process of diffusion.

This oxygen is used in respiration in the cells of the leaf. The carbon dioxide produced during respiration diffuses out from the leaf into air through the same stomata.

 

Respiration in Roots

The roots of a plant are under the ground but root cells also need oxygen to carry out respiration and release energy for their own use.

The roots obtain oxygen for breathing and respiration from the soil.

Air is present in-between the particles of soil roots of a plant have a very large number of tiny hair on them

The roots of a plant take up air from the spaces between the soil particles. Actually the roots of a plant have a very large number of tiny hair on them which are called root hair. The root hair are in contact with the air in the soil particles.

Oxygen from air in soil particles diffuses into root hair and reaches all the cells of the root where it is utilised in respiration. Carbon dioxide produced in the cells of the root during respiration goes out through the same root hair by the process of diffusion.

The respiration in roots occurs by the exchange of gases (oxygen and carbon dioxide) through the root hair.

If a potted plant is over-watered for a long time, then the plant may ultimately die. This is because too much water expels all the air from in-between the soil particles. Due to this, oxygen is not available to the roots for aerobic respiration. Under these conditions, the roots of plant respire anaerobically producing alcohol. This may kill the plant.

Plants carry out photosynthesis (for making food) only during the day time when sunlight is available.

Plants carry out respiration (to obtain energy) during the day time as well as at night (because they require energy all the time).