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

Of the eight nuclei formed in the embryo sac, six become organised into cells.

1. What term is given to the other two nuclei?
2. Name the cell in which they are present.

What do you understand by commaless in genetic code.

Mention two factors, which the harmful effects of air pollutants on living beings, depend on.

Give the other name of Jhum cultivation.

In a dihybrid cross, when would the proportion of parental gene combinations be much higher than non–parental types, as experimentally shown by Morgan and his group?

What is the old name of RCH programmes? When was it initiated in India?

Millions of chickens were killed in West Bengal, Orissa and Maharashtra recently. What was the reason?

How much of productivity is contributed by oceans?

What represents the dominance of RNA world?

Name two diseases whose spread can be controlled by the eradication of Aedes mosquitoes.