Heredity

How many chromosomes are there in humans?

The number of chromosome pairs, found in the cells of human body is–

Assertion (A): In human being, the females play a major role in determining the sex of the offspring. Reason (R): Women have two 'X' chromosomes.

Male's gene constituent is–

Which combination of chromosomes in mankind give birth to a male child?

Which of the following professional(s) are more likely to run the risk of a permanent change in their cell's DNA? 1. Researchers using carbon 14 isotope 2. X-ray technician 3. Coal miner 4. Dyer and painter