Chromosomes are made up of
$DNA$ only
$RNA$ and $DNA$
$DNA$ and histone
Only histones
Nicotiana sylvestris flowers only during long days and $N$.tabacum flowers only during short days, if raised in the laboratory under different photoperiods, they can be induced to flower at the same time and can be cross fertilized to produce self-fertile offspring. What is the best reason for considering $N .$ sylvestris and $N$. tobaccum to be separate species?
Albinism is known to be due to an autosomal recessive mutation. The first child of a couple with normal skin pigmentation was an albino. What is the probability that their second child will also be an albino
Sometimes the separation of twins is incomplete and these are borne attached are remain so even after. Such twins are known as
The reduction of one pair of chromosome in human is due to
Which of the following is regarded as Drosophila of the fungal world