Science
Mendelian genetics.
Definition
Mendelian genetics describes the patterns of inheritance first discovered by Gregor Mendel through his experiments with pea plants. It includes the Law of Segregation (each organism has two alleles that separate during gamete formation) and the Law of Independent Assortment (genes on different chromosomes sort independently).
Examples
Real-world.
- 1 Crossing two heterozygous tall pea plants (Tt × Tt) produces a 3:1 phenotypic ratio of tall to short offspring
- 2 A dihybrid cross (RrYy × RrYy) yields a 9:3:3:1 phenotypic ratio in the F2 generation
- 3 Human earlobe attachment (free vs. attached) is often used as a simple example of dominant-recessive inheritance
Key Fact
Monohybrid cross: 3:1 phenotypic ratio; Dihybrid cross: 9:3:3:1 phenotypic ratio in F₂.