4. Black fur is a dominant trait. Two black cats mate and produce 6 black kitens

Question

4. Black fur is a dominant trait. Two black cats mate and produce 6 black kitens and 2 white kittens. What are the genotypes and phenotypes of the parent cats? a. b. What is the genotype of the white kittens? Assume that the 'Parent Male cat mates with a white cat What are the chances of producing white kittens? Show me. c. d. Assume that the 'Parent Female cat mates with a different, male black cat to produce 4 black kittens and no white kittens. Can you definitively give me the male's genotype? Explain.

Explanation / Answer

Given here is phenotype of parent cats is black. When they mate they produce both black fur kittens and white fur kittens .

Also, black fur is dominant over white fur.

In order to produce white fur, both the parent must tansmit the recessive allele in the offspring. This statement suggests that both the parents are heterozygous for the allele.

Let the dominant allele be denoted as B and recessive as b.

A). Both the parents are black and heterozygous so their genotype is Bb. Phenotype is black fur.

B). A recessive allele is always expressed in homozygous condition. Here the kittens are white so their genotype will be bb.

C). If parent male cat with genotype Bb mates with white cat, that is, bb, we get Bb X bb= 2Bb and 2bb. Here the chances of producing white kittens is 50% or 0.5.

D). If female cat with genotype Bb mates with male with genotype BB, Then only black offspring will be produced. This is the only possibility of getting black kitten and no white kitten.

So the genotype of different black male is definitely BB.

Related Questions

Navigate

• Browse (All)
• Browse 4
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.