Q21 of 26 Page 1

How does tissue culture help in growing explants into independent plants? Write any two advantages of growing crops by tissue culture.

Explants are any part of a plant taken out and grown in a test tube, under sterile conditions in a special nutrient media.


The capacity to generate a whole plant from any cell/explants is called totipotency.


The nutrient medium must provide a carbon source such as sucrose and also inorganic salts, vitamins, amino acids and growth regulators like auxins, cytokinins, etc. By application of these methods, it is possible to achieve propagation of a large number of plants in very short durations.


Advantages of growing crops by tissue culture –


• It is a very fast technique.


• Very little space is needed for developing new plants.


• The crops grown by tissue culture are disease-free.


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(b) Mention any two negative effects of loss of biodiversity in the region where it occurs.


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Describe the Secondary/Biological treatment given to the sewage water before it can be released into natural water bodies.

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(a) List any two ways in which you can try to bring in awareness amongst the students of your age group to reduce air pollution in your city.


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