CBSE 10th Biology | Life Processes | Questions and Answers based on Nutrition


Questions and Answers based on Nutrition

Question:

Name the process by which plants make food.

Answer:

Photosynthesis

Question:

Where do plants get each of the raw materials required for photosynthesis ?

Answer:

CO2 from atmosphere and water from the soil.

Question:

(a) Name the gas used in photosynthesis.

(b) Name the gas produced in photosynthesis

Answer:

(a) CO2 (Carbon dioxide)

(b) Oxygen (O2)

Question:

What kind of nutrition occurs in fungi ?

Answer:

Saprophytic

Question:

What is the end products of anaerobic respiration in yeast ?

Answer:

C2H5OH

Question:

What are the differences between autotrophic nutrition and heterotrophic nutrition ?

Answer:

S.No. Autotrophic Heterotrophic
1. Organisms prepare their own food from inorganic raw materials. Organism get their food prepared by autotrophs or from other organic resources.
2. For example : Plants For example : Fungi and animals

Question:

What is the role of the acid in our stomach ?

Answer:

The acid i.e. HCl secreted by gastric glands in our stomach creates an acidic medium. In acidic medium, enzymes pepsinogen gets converted into active pepsin. It also kills microorganisms and sterilizes food.

Question:

What are the functions of bile juice ?

Answer:

Bile juice which is secreted from the liver makes the medium of the intestine alkaline so that pancreatic enzymes can act on the food. The other function of the bile is to break the large molecules of fats into small one or to emulsify fat to increase the surface area so that enzymes can work efficiently.

Question:

What are the functions of digestive enzymes ?

Solution:

Digestive enzymes help in the breakdown of complex food particle into simpler soluble forms that can be absorbed by body cells. The enzymes help in the digestion process in the following ways :

1.    The carbohydrate digesting enzymes (e.g. amylase) break down carbohydrate into its monomeric form such as glucose, fructose etc.

2.    The protein digesting enzymes (e.g. pepsin, trypsin etc.) converts protein into amino acids.

3.    The fat digesting enzymes (e.g. lipase) converts fat into fatty acids and glycerols.

Question:

Explain how exchange of gases takes place in plants.

Answer:

Plants exchange gases through small openings called stomata by the process called diffusion. During day time CO2 is taken in as in the photosynthesis CO2 is required in a large amount and O2 which is produced in the process of photosynthesis is given out. In the night, when there is no photosynthesis occurring, CO2 is released which is produced in the process of respiration and O2 is taken in.

Question:

Explain the structure of stoma. Discuss its mechanisms.

Answer:

Stoma is a small pore, present ion the surface of leaf. They are surrounded by two guard cells, which is bean shaped in case of dicot and dump bell shaped in monocots. The inner wall facing the stoma are thicker than the outer walls. Guards cells are surrounded by subsidiary / epithelial cells.


Opening and Closing of Stomatal Pore :     The opening and closing of the pore is a function of the guard cells. The guard cells swell when water flows into them causing the stomatal pore to open. Similarly the pore closes if the guard cells shrink. As large amount of water is lost through stomata, the plant closes these pores.


(a) Open and (b) closed stomatal pore

Question:

Draw a well labeled and neat diagram of V.S of leaf showing chloroplast.

Answer:


The structure of a leaf to show chloroplasts in it

(The small circles in the above diagram are all chloroplasts).

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