The law of dominance was proposed by which scientist?

• A. Mendel
• B. Darwin
• C. Watson
• D. Crick

Answer: (A)

Dominant and recessive traits come from different versions of a gene, called alleles. Gregor Mendel, through careful pea-plant experiments, showed that some alleles mask others in the offspring. When an organism inherits a dominant allele along with a recessive one, the dominant trait is expressed in the phenotype. The recessive trait only appears when both alleles are recessive.

This identification of how a dominant allele can hide the recessive one is what the law of dominance is all about. Mendel built his conclusions by tracking traits across many crosses and noticing consistent patterns in how traits appeared generation after generation.

Darwin proposed natural selection as the mechanism for evolution, not how traits are inherited, and Watson and Crick described the structure of DNA, not dominance relationships in inheritance.