A recessive gene can be expressed if the genotype is:
Correct answer: A. Homozygous recessive
- A. Homozygous recessive
- B. Homozygous dominant
- C. Heterozygous
- D. (B) and (C)
Explanation
Only individuals with an aa genotype will express a recessive trait; therefore, offspring must receive one recessive allele from each parent to exhibit a recessive trait.
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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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