Question

Bos indicus, a species of cattle, has a 2n=60:

How many chromosomes does a calf receive from the bull?

How many autosomes are present in each somatic cell?

How many chromosomes are present in Metaphase I?

How many chromosomes are present in Anaphase II?

How many chromosomes are present in an ovum (egg)?

Answer 1

Answer :

1)

2n = 60

Calf receives haploid chromosomes from bull.

So n = 30

Calf receives 30 chromosomes from bull.

2)

Autosomes are non sex chromosomes.

All somatic cells contain

autosomes = 60 - allosomes

= 60 - 2 = 58 allosomes in all somatic cells.

3)

In metaphase I chromosomes will be 2n that is diploid. But chromatids will be doubled.

So chromosome number in metaphase I is 60.

4)

In anaphase II chromosomes will be 2n. The number is restored from n after metaphase II.

So chromosomes are 60.

5)

In an egg there will be haploid number of chromosomes.

So 30 chromosomes.