Question

What do you mean by the line that for each trait there will be two versions in each child..Ncert class 10 herediry and evolution

Answer 1

Trait mean An inherited character or features like sometimes if both your parents or any one of them is tall it is most likely that you will be tall too but in some cases child will not be tall because every trait has two Allele like for height we denote is as TT as tall , Tt as also tall but not pure tall and tt as short . So there are both possibilities if your parents has either Tt and Tt set of allele or Tt and tt set of allele, there are some chances that you'll be short but majorly you'll be tall (  not in 2nd set of allele)

I hope it helps if not please feel free to ask :)