If a gene is fixed in a population:a)it cannot undergo mutation. b) it is located near the centromere on the chromosome, reducing its ability to recombine it cannot undergo mutation c) only one allele appears for that gene in that population.

C. Only one allele appears for that gene in that population.

Explanation:

This totally explains what happens during gene fixation because when it happens in a small population, it tends to make one of its allele to appear for the said gene.

Furthermore, fixation can be explained as the change in a gene pool from a situation where there exists at least two variants of a particular allele to a situation where only one of the alleles is left. In the absence of mutation, any allele must eventually be fixed or lost completely from the population. Whether a gene will ultimately be lost or fixed is dependent on selection coefficients and chance fluctuations in allelic proportions.

c. only one allele appears for that gene in that population.

Explanation:

A fixed gene is one whose alternate forms are not present within the population.

The alternate form of a gene are known as alleles. A fixed gene only has one type of allele within the entire population and hence, has no alternate forms.

The correct option is c.

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