A farmer who wants to get into the milk business has bought a small beginning he

Question

A farmer who wants to get into the milk business has bought a small beginning herd of 12 cows all of which produce high quantities of milk (M, dominant over low quantities) and have high fertility (F, also dominant over low fertility). However, she knows that all of her cows are heterozygous for both these traits and that the genes are linked. In her cows, one homolog of the pair contains the dominant alleles for each trait and one contains the recessive allele of each of the traits. Two of the farmer's nearby neighbors own bulls that are also heterozygous for these traits. The first neighbor's bull has the same alleles linked as her cows but the second neighbor's bull has one dominant and one recessive allele from each trait on each homolog. Assume that the two genes are so close together that no recombination (crossing over) occurs between them

Baring in mind that the farmer would like to obtain the maximum number of calves with high milk production and high fertility, which of the two available bulls should she choose to introduce her cows to (neighbor 1 or neighbor 2)?

What percentage of the offspring resulting from the above match will have the most desirable phenotype of high milk production and high fertility? %

What percentage of the offspring resulting from the above match will have the most desirable genotype of MMFF? %

Explanation / Answer

The cows and bulls are heterozygous ..........................MmFf

cows have a genotype: MF on one chromosome and mf on another chromosome.

first bull have a genotype: MF on one chromosome and mf on another chromosome

second bull have a genotype:Mf on one chromosome and mF on another chromosome

If there is a cross between the cow and first bull:

genotype: 1:2:1

phenotype: 3 are with high milk and high fertility (75%) and 1 with low milk and low fertility (25%).

When a cross is made between the cow and second bull:

genotype:1:1:1:1

phenotype: high milk and high fertility (50%), high milk low fertility (25%), low milk and low fertility(25%)

which of the two available bulls should she choose to introduce her cows to (neighbor 1 or neighbor 2) for high milk production and high fertility?

First bull

What percentage of the offspring resulting from the above match will have the most desirable phenotype of high milk production and high fertility? %

75%

What percentage of the offspring resulting from the above match will have the most desirable genotype of MMFF? %

25%

MF mf MF MMFF(high milk and fertility) MmFf (high milk and good fertility) mf MmFf (high milk and good fertility) mmff (low milk and low fertility)

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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