Question

i) Draw a well-labelled diagram to show the metaphase stage of mitosis in an animal cell having four chromosomes.
ii) Mention any two reasons for the population explosion in India.
iii) Give biological reasons for the following.
1) The pituitary gland is also known as the master gland.
2) Gametes have a haploid number of chromosomes.

Answer 1

ii) The reason for population control is as followed

1. The desire for a male child.
2. Lack of awareness about birth control measures.
iii) 1. The pituitary gland secretes hormones that regulate all other endocrine glands so it is called the master gland.
2. Gametes are produced by meiosis in which the number of chromosomes gets reduced to half. So they are haploid. During fertilisation, the zygote has a diploid number of chromosomes.