Science (English Medium) इयत्ता १२ - CBSE Question Bank Solutions for Biology

Write the function of adenosine deaminase enzyme.

Expand the Given and mention one application of each:

PCR

Mention the difference in the mode of action of exonuclease and endonuclease.

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

Draw a diagrammatic sectional view of the female reproductive system of human and label the parts

(i) where the secondary oocytes develop

(ii) which helps in collection of ovum after ovulation

(iii) where fertilization occurs

(iv) where implantation of embryo occurs.

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

Suggest a technique to a researcher who needs to separate fragments of DNA.

How are the following formed and involved in DNA packaging in a nucleus of a cell?

Differentiate between Euchromatin and Heterochromatin.

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

Name the transcriptionally active region of chromatin in a nucleus.

Recombination DNA−technology is of great importance in the field of medicine. With the help of a flow chart, show how this technology has been used in preparing genetically engineered human insulins.

State the role of C-peptide in human insulin.

Name the enzymes that are used for the isolation of DNA from bacterial and fungal cells for recombinant DNA technology.

How does a restriction nuclease function? Explain

The following graph shows the species-area relationship. Answer the following questions as directed.

(a) Name the naturalist who studied the kind of relationship shown in the graph. Write the observations made by him.

(b) Write the situations as discovered by the ecologists when the value of ‘Z’
(Slope of the line) lies between:

1. 0.1 and 0.2
2. 0.6 and 1.2

What does ‘Z’ stand for?

(c) When would the slope of the line ‘b’ become steeper?

Name and describe the technique that helps in separating the DNA fragments formed by the use of restriction endonuclease

Explain, giving three reasons, why tropics show greatest levels of species diversity.

Draw a labelled diagram of the female reproductive system.

Write two major functions of ovary.