Biotechnology: Principles and Processes — BIOLOGY STD 12 Science — Question

How does colostrum provide initial protection against diseases to newborn infants? Give one reason.

(i) The human male ejaculates about 200 to 300 million sperm during a coitus, however the ovum is fertilized by only one sperm. How does the ovum block the entry of additional sperms?
(ii) All copulations will not lead to fertilization. Why?

Micropropagation is a method of producing new plants in a short duration using plant tissue culture.

The pyramid of energy is always upright. Why?

Do you think that reproductive health in our country has improved in the past 50 years? If yes, mention some such areas of improvement.

A woman of 47 years delivered an abnormal child with a flattened nasal bridge and mouth partially open with a large protruding tongue. Name this genetic abnormality. What causes this condition?

How is commensalism different from predation, though one of the partners is benefitted in each of them?

1. Why are the plants raised through micropropagation termed as somaclones?
2. Mention two advantages of this technique.

Make a chart (with diagrammatic representation) showing a restriction enzyme, the substrate DNA on which it acts, the site at which it cuts DNA and the product it produces.