Question about Genetics?

Question

1. How many different kins of offspring could result if one parent is pure dominant and the other is parent is pure recessive? How many different kinds of offspring could result if both parents are heterozygous?

2. Why does an individla usally carry only two genes for a certain trait?

3. Why do living organisms have an even number of chromosome in their body cells?

Answer 1

1a one dom and one rec-1
1b two hetero-3
2 if there is just one gene for a trait, an individual can only have two dif possible genes for that trait
3. most organisms have 2 copies of each chromosome