Comb shape in chickens represents one of the classic examples of gene interaction. Two gene pairs interact to influence the shape of the comb. The genes for rose comb (R) and pea comb (P) together produce walnut comb. The fully homozygous recessive condition (rrpp) produces the single comb. Assume that a rose-comb chicken is crossed with a walnut-comb chicken and the following offspring are produced: 17 walnut, 16 rose, 7 pea, 6 single. What are the probable genotypes of the parents?

Explanation:

Given:

Gene for rose comb= R;

Gene for pea comb= P;

R and P gene together produce walnut comb;

rrpp gene produce single comb.

calculation;

Rose comb is crossed with walnut comb chicken

offspring are,

Walnut= 17

rose= 16,

pea= 7,

single = 6

For producing such offspring, the genotypes of the parents are Rrpp x RrPp.

Offspring are= RRPp, RRpp,Rrpp, RrPp, rrPp, rrpp etc

his research revealed two genetically different groups of prokaryotes, which justified splitting kingdom monera into two kingdoms. the genetic and cellular differences were so great, that these two kingdoms were eventually placed into different domains in the current three-domain system.

bc blah

explanation:

bc blah