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A plant with round seeds is crossed with another plant with round seeds. Round are dominant over oval seeds. When two heterozygous round-seeded plants are crossed, what is expected of their offspring, assuming random chromosome segregation?

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there is a 75% chance of it being round and a 25% chance of an oval seed. your combinations would be MM,Mm,Mm,mm.
User Ardrian
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Answer:

It is expected that 75% of the offspring have the dominant gene and have round seeds, while 25% have only the recessive gene with oval seeds.

Step-by-step explanation:

To know the possible allelic combinations of offspring we will need to do the Punnet Square.

Punett's picture should be constructed by placing in the first column the possible gametes of one individual and, in the first row, the possible gametes of the other individual (as shown in the figure below). Then the combination of these gametes is made.

As we know, the dominant allele "A" represents the round seeds, while the recessive allele "a" represents the oval seeds.

When we fill in the punnet square for the two peas shown in the question above, we will see that 3/4 of the offspring have the dominant gene (and hence will be round seeds), while 1/4 of the offspring has only the recessive allele (and therefore , will be oval seeds). With this we can conclude that 75% of the offspring will have round seed while 25% will have oval seed.

A plant with round seeds is crossed with another plant with round seeds. Round are-example-1
User Henrik H
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