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If a person has a dominant allele for brown eyes and a recessive allele for blue eyes, which

statement is correct?
Group of answer choices

The individual has brown eyes

The individual has blue eyes

The individual has eye color that is a mix of brown and blue

Eye color cannot be determined based on the given information

User Don Tomato
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1 Answer

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Answer:

hey jodu!

Step-by-step explanation:

The answer is The individual has brown eyes.

Light eyes start from recessive genes. That is, it is at a disadvantage with respect to darker shades (that is why the brown color is dominant over green or blue). But to understand why a person has clear eyes, one must pay attention not only to the color of their parents' eyes, but also to that of their grandparents, since the location of the gene comes into play here.

In other words, recessive genes can "survive" the dominant genes determined from where they are located. The fact that women have two X chromosomes allows recessive genes to be inherited equally. For a pure color to be given, all genes have to be the same. If not, they had a mixed color.

Although there are always three types of colors (brown, green and blue), humans have many phenotypic variations in eye color. It is a complex process involving several factors. For example: the color of the eyes also depends on the amount of the melanin pigment in the iris (the colored part of the eye), which will determine its hue.

The more pigment, the darker the eyes. Blue, gray and green eyes are lighter because they have less melanin in the iris. For example: between a father with brown eyes and a mother with green eyes, a mixed color is very unlikely because the brown color contributes a large amount of melanin and the very little green.

Most people in the world have brown eyes. The next most common colors are blue and gray, with green being the least frequent color (only 2% of the world's population has green eyes).

How are the chromosomes that influence the color of the eyes

The genetic information referring to the color of the eyes is transmitted through not one, but two chromosomes: chromosomes 15 and 19.

There are different versions of the same gene. Those different versions are called alleles. The alleles are responsible for a person having a chromosome with the gene for the color blue in the eyes and another gene for the color brown on the homologous chromosome. The blue and brown colors are the alleles.

A human being can have two equal alleles in homologs, or two different. That is, the two genes can be for the color blue or both can be for the brown. You can also carry one gene for blue and one for brown. Individuals who have the same allele on both chromosomes are called homozygotes, and those who have different alleles are called heterozygous.

As we explained before, alleles can also be dominant or recessive. A dominant allele always manifests itself, even if the individual has only one of the chromosomes and that of the homologous chromosome is different. A recessive allele is only shown if there are two copies of it, that is, if it is on both chromosomes.

The blue-eyed allele is recessive and two copies are needed for the person to have blue eyes. However, to have brown eyes, it is enough that only one of the chromosomes bears the allele gene.

User Jhonny
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