1. Law of Segregation:
* Concept: Each individual carries two alleles (alternative forms of a gene) for each trait, and these alleles separate during gamete formation (sperm and egg cells). Each gamete receives only one allele from the pair.
* Example: A pea plant with the alleles "YY" for yellow seeds will produce gametes with either "Y" or "Y".
2. Law of Independent Assortment:
* Concept: Alleles for different traits (e.g., seed color and seed shape) separate independently of each other during gamete formation. This means that the inheritance of one trait doesn't influence the inheritance of another.
* Example: A plant with yellow seeds (YY) and round seeds (RR) will produce gametes with different combinations of alleles: YR, Yr, yR, and yr.
3. Dominant and Recessive Alleles:
* Concept: One allele (the dominant allele) can mask the expression of another allele (the recessive allele).
* Example: In pea plants, the allele for yellow seeds (Y) is dominant over the allele for green seeds (y). A plant with the genotype "Yy" will have yellow seeds because the dominant Y allele masks the recessive y allele.
4. Genotype and Phenotype:
* Concept: Mendel distinguished between the genetic makeup of an organism (genotype) and its observable characteristics (phenotype).
* Example: A plant with the genotype "Yy" has the phenotype of yellow seeds, even though it carries the allele for green seeds.
These fundamental principles laid the foundation for our understanding of inheritance and continue to be relevant in modern genetics. Mendel's work was revolutionary, providing the first insights into how traits are passed from one generation to the next.
