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

Mention the evolutionary significance of the Homo erectus

Where in the fallopian tube does fertilization occur in humans?

Describe the development of a fertilized ovum upto implantation.

How does restriction endonuclease function?

Although a prokaryotic cell has no defined nucleus, yet DNA is not scattered throughout the cell. Explain.

Explain the roles of the following with the help of an example each in recombinant DNA technology :

Restriction Enzymes

Explain divergent evolution with two examples. 

Explain the role of histones in forming a nucleosome.

Draw a label diagram.
Draw a sectional view of the human ovary showing the different stages of developing follicles, corpus luteum, and ovulation.

Answer the following question.
Explain the significance of palindromic nucleotide sequence in the formation of recombinant DNA.

Answer the following question.
Write the use of restriction endonuclease in the formation of recombinant DNA.

Draw a sectional view of the human ovary. Label the following parts :

Give a reason why :
Single cloning site is preferred in a vector.

State the medicinal value and the bioactive molecules produced by Penicillium notatum.

State the medicinal value and the bioactive molecules produced by Monascus purpureus.

State the medicinal value and the bioactive molecules produced by Trichoderma polysporum.

Answer the following question based on Meselson and Stahl's experiment on E. coli :

Write the name of the chemical substance used as the only source of nitrogen in the experiment.

Name the microbes that help the production of the following product commercially:
Statin

Name the microbes that help the production of the following product commercially:
Penicillin

The part of fallopian tube closest to the ovary is ______.