Final answer:
Donte' inherited the gene for color blindness from his mother, as color blindness is a sex-linked recessive trait carried on the X chromosome, and males can only inherit this X chromosome from their mothers.
Step-by-step explanation:
Color blindness is a sex-linked recessive trait, and the gene responsible for this condition is located on the X chromosome. Males have one X chromosome and one Y chromosome (XY), whereas females have two X chromosomes (XX). If a male is color blind, it means that his single X chromosome carries the gene for color blindness. A female carrier, who has one normal X chromosome and one with the gene for color blindness, will typically not exhibit the trait since it is recessive. Therefore, Donte' must have inherited the gene for color blindness from his mother, as his father's Y chromosome does not carry the gene for color vision.
To further illustrate this, consider the Punnett square:
Mother's Genotype: XcX
Father's Genotype: XY
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- Xc X - Carrier daughter
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- Xc Y - Color blind son
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- XX - Unaffected daughter
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- XY - Unaffected son
Here, 'X' represents the normal allele for color vision and 'Xc' represents the color blind allele. Since Donte' is color blind and male, he can only have the genotype 'XcY', indicating that the 'Xc' allele was inherited from his mother. The father can only contribute the 'Y' chromosome towards his son's sex chromosomes.
For a female to become color blind, she must inherit two copies of the color blindness gene, one from each parent, making the condition much rarer in females. A male cannot be a carrier of the trait because he has only one X chromosome; if it carries the gene for color blindness, he will express the trait.