Question

it is the contribution of father determines the sex of a newborn. explain

Answer 1

Yes the sex of a newborn baby is decided by the the chromosome that he gets from his father as the mother/female has same XX chromosome and father /male has different XY chromosome so the child receives one X chromosome from his mother and if it receives X chromosome then the child will be a daughter (with chromosome XX) and if it receives Y chromosome then the child is a son ( with chromosome XY)
Hope this helps you....

Answer 2

Yes
There will be 23 pairs of chromosomes in every cell..
From mother foetus gets all x type
From father foetus gets both x and y type... If both x's combine ,sex is female
And if x and y combine , sex is male