Sexual Reproduction in Flowering Plants — BIOLOGY STD 12 Science — Question

Give the sum total of all the allelic frequencies in a stable population. List any two factors which disturb the stability of a population. How does this disturbance affect the population?

List the key tools used in recombinant DNA technology.

A culture plate of Lactobacillus shows blue-coloured colonies and colourless colonies. Explain the principle involved in the formation of such variance in the colour of colonies.

It is established that RNA is the first genetic material Explain

A woman has certain queries as listed below, before starting with contraceptive pills. Answer them.

1. What do contraceptive pills contain and how do they act as contraceptives?
2. What schedule should be followed for taking these pills?

1. What precaution(s) would you recommend to a patient requiring repeated blood transfusion?
2. If the advise is not followed by the patient there is an apprehension that the patient might contract a disease that would destroy the immune system of his/her body.

Explain with the help of schematic diagram only how the immune system would get affected and destroyed.

The egg of an animal contains 10 pairs of chromosomes, of which one is X-chromosome. How many autosomes would there be in the karyotype of this animal?

Explain any one use of biotechnology in medicine.

What are the various public health measures, which you would suggest as safeguard against infectious diseases ?

How do you consider tendrils of Cucurbita and thorns of Bougainvillea as homologous structure?