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In males, the gene for color blindness is present in:

Correct answer: A. X-chromosome

  • A. X-chromosome
  • B. None of these
  • C. Y-chromosome
  • D. Both X and Y chromosomes

Explanation

The gene for colour blindness is present on the X chromosome. As males have XY chromosomes, their X chromosome is inherited from their mothers whereas females have XX chromosomes, their X chromosomes are inherited by their fathers and mothers. So males are more likely to be affected by colour blindness because they need one faulty gene on their X chromosome to be colour blind and females need two faulty genes in this case.

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About Inheritance

Mendel's laws explain segregation, independent assortment and the prediction of genetic ratios using alleles, genotypes and phenotypes. The chapter also covers linked genes, recombination and crossing over during meiosis, then applies pedigree reasoning to X-linked recessive traits, which show different inheritance patterns in males and females.

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