allery**Pleiotropy** is best described as:
ATwo genes controlling one trait
BOne gene controlling two or more different traits
CTwo pairs of contrasting alleles
DMultiple alleles at a single locus
Answer & Solution
Correct answer: B. One gene controlling two or more different traits
A pleiotropic gene controls multiple, apparently unrelated traits.
Sickle-cell anaemia is a classic example — the Hb^s allele causes anaemia, organ damage, AND confers malaria resistance.
Multiple alleles is a distinct concept (different versions of one gene).
Keep practising Unit 5C: Non-Mendelian Genetics & Population Transmission
Browse all Unit 5C: Non-Mendelian Genetics & Population Transmission questions for AP Biology, or explore more Biology topics.
Related questions
Which of the following is **not** a stop codon?The semiconservative nature of DNA replication was experimentally proved by:The F₂ **genotypic** ratio in Mendel's monohybrid cross is:In Mendel's monohybrid cross between true-breeding tall (TT) and dwarf (tt) plants, the F₂Mendel conducted his hybridisation experiments on which plant?In the Watson-Crick double helix, adenine pairs with thymine via how many hydrogen bonds?In birds, the sex-determination mechanism is:Down syndrome in humans is caused by