In human males and females, how many pairs of chromosomes are identical?

In the following crosses,write the characteristics of the progeny:

Cross	Progeny
$(a)$ $RR YY \times RR YY$ (Round,yellow $\times$ Round,yellow)	..........
$(b)$ $Rr Yy \times Rr Yy$ (Round,yellow $\times$ Round,yellow)	..........
$(c)$ $rr yy \times rr yy$ (Wrinkled,green $\times$ Wrinkled,green)	..........
$(d)$ $RR YY \times rr yy$ (Round,yellow $\times$ Wrinkled,green)	..........

Does geographical isolation of individuals of a species lead to formation of a new species? Provide a suitable explanation.

$(a)$ What are monohybrid and dihybrid crosses?
$(b)$ How did Mendel prove that tallness is the dominant trait and dwarfness is the recessive trait in a pea plant? Explain with the help of a monohybrid cross.

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.

$(a)$ Why do we say that homozygous plants produce pure progeny?
$(b)$ Define heterozygous.
$(c)$ Explain how the process of speciation takes place.