Science (English Medium) कक्षा १२ - CBSE Important Questions for Biology

Name any two techniques used to detect the cancer of internal organs and write about any one of them.

Immunotherapy these days is one of the most efficient ways of treatment of cancer. The therapy involved activates the immune system and destroys the tumour.

1. Write an example of one such biological response modifier used in immunotherapy.
2. Why do patients need such substances if immune system is already working in body?
3. State what is 'Contact inhibition'.

A patient was advised to have a kidney transplant. To suppress the immune reaction, the doctor would administer him ______.

Explain the role of Primary and Secondary Lymphoid organs with the help of suitable examples.

Name a genus of baculovirus.

How do organic farmers control pests?

Explain enzyme – replacement therapy to treat adenosine deaminase deficiency. Mention two disadvantages of this procedure.

Name and explain the type of interaction that exists in mycorrhizae and between cattle egret and cattle.

Why do children cured by enzyme-replacement therapy adenosine deaminase deficiency need periodic treatment?

Explain the different steps involved during primary treatment phase of sewage.

Explain the process of secondary treatment given to the primary effluent up to the point it shows significant change in the level of biological oxygen demand (BOD) it.

Write the function of adenosine deaminase enzyme.

Expand the Given and mention one application of each:

PCR

Why are the fruit juices bought from market clearer as compared to those made at home?

Name the bioactive molecules produced by Trichoderma polysporum and Monascus purpureus.

Name the source of streptokinase. How does this bioreactor molecule function in our body?

How do mycorrhizae act as biofertilizers? Explain.

Suggest any two possible treatments that can be given to a patient exhibiting adenosine deaminase deficiency.

Explain the function of “anaerobic sludge digester” in a sewage treatment plant.

Mention one advantage and one disadvantage to a farmer who uses them.