Question

In horses, black is dominant to chestnut and trotting is dominant to pacing. A heterozygous black and h o m o zygous pacer is crossed with chestnut and heterozygous trotting. What is the number of black pacers in a population of 260,000

Answer 1

65,000

Step-by-step explanation:

Black (B) is dominant to chestnut (b)

Trotting (T) is dominant to pacing (t)

A heterozygous black and h0m0zygous pacer (Bbtt) is crossed with a chestnut and heterozygous trotting (bbTt)

Bbtt x bbTt is the cross.

Potential alleles - Bt and bt bT and bt

Punnett square attached

Possible genotypes are: BbTt, bbTt , Bbtt, bbtt

Black pacers have the genotype BBtt or Bbtt

1:4 of the offspring have The Bbtt genotype.

If there are 260,000 in the population, then 260,000 / 4 would be black pacers.

260,000/4 = 65,000