With green pods as a dominant trait over yellow, which of the following crosses will result in all progeny having yellow pods?a)Homozygous green and homozygous yellowb)Heterozygous green and heterozygous greenc)Homozygous yellow and homozygous yellowd)Homozygous green and homozygous greenCorrect answer is option 'C'. Can you explain this answer?

Question

Answer

Yellow being recessive will express only when both alleles are present. That occurs only when both parents can contribute an allele encoding for the yellow pod. For all progeny to have yellow pods, both parents have to be homozygous for yellow pods.

Answer

Explanation:

When it comes to the inheritance of traits, there are different patterns that can occur. One of these patterns is known as Mendelian inheritance, which follows the laws proposed by Gregor Mendel.

In this question, we are dealing with the inheritance of pod color in a plant species. Green pods are dominant over yellow pods, which means that if an individual has at least one green allele, it will have green pods. On the other hand, an individual needs to have two yellow alleles in order to have yellow pods.

Homozygous vs Heterozygous:

- Homozygous individuals have two identical alleles for a particular trait. In this case, homozygous green individuals have two green alleles, and homozygous yellow individuals have two yellow alleles.
- Heterozygous individuals have two different alleles for a particular trait. In this case, heterozygous green individuals have one green allele and one yellow allele.

Crosses:

a) Homozygous green and homozygous yellow:
If we cross a homozygous green individual with a homozygous yellow individual, all the progeny will be heterozygous green. This is because the offspring will inherit one green allele from the green parent and one yellow allele from the yellow parent. Therefore, none of the progeny will have yellow pods.

b) Heterozygous green and heterozygous green:
If we cross two heterozygous green individuals, there is a 25% chance of obtaining progeny with yellow pods. This is because in this cross, there is a 25% chance of inheriting two yellow alleles, resulting in yellow pods.

c) Homozygous yellow and homozygous yellow:
If we cross two homozygous yellow individuals, all the progeny will have yellow pods. This is because both parents only have yellow alleles to pass on to their offspring.

d) Homozygous green and homozygous green:
If we cross two homozygous green individuals, all the progeny will have green pods. This is because both parents only have green alleles to pass on to their offspring.

Therefore, the only cross that will result in all progeny having yellow pods is the cross between homozygous yellow individuals (option C).

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