In human males and females, how many pairs of chromosomes are identical (in $pairs$)?

Name any five vegetables generated from a common ancestor through artificial selection rather than natural selection. Also,mention the features for which each vegetable is selected.

In peas,a pure tall plant $(TT)$ is crossed with a short plant $(tt).$ The ratio of pure tall plants to short plants in $F_{2}$ is

What is the scientific name of the human species?

Give reasons why acquired characters are not inherited.

New species may be formed if
$(i)$ $DNA$ undergoes significant changes in germ cells
$(ii)$ chromosome number changes in the gamete
$(iii)$ there is no change in the genetic material
$(iv)$ mating does not take place