# Eye color is determined by a person's genes. If R represents the gene for brown eyes and I represent the gene for blue eyes answer the following:    Consider the offspring of a parent with a...

Eye color is determined by a person's genes. If R represents the gene for brown eyes and I represent the gene for blue eyes answer the following:

Consider the offspring of a parent with a homozygous brown-eyed RR gene combination and a parent with a heterozygous brown-eyed RI gene combination. What percent of the possible genetic combinations result in brown-eyed offspring? What percent of the possible genetic combinations are carriers for the blue-eyed gene?

justaguide | College Teacher | (Level 2) Distinguished Educator

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The color of a person's eyes depends on the genetic configuration. The gene responsible for brown eyes is denoted by R and that blue eyes is denoted by I.

A person with only the R gene has brown eyes. A person with both the R and the I gene has brown eyes if the R gene is dominant and blue eyes if the I gene is dominant.

The offspring of a parent with RR gene combination and another with RI gene combination can have the following gene combinations:

RR, RR, RI, IR

........R........R

R      RR      RR

I       IR       RI

There is a 75% probability that the offspring has brown eyes. The probability that the offspring has blue eyes is 25%. The probability that the offspring is a carrier for the blue-eyed gene is 50%.