Final answer:
Parents pass genes to their offspring that contain alleles responsible for inherited traits. Gregor Mendel's experiments with pea plants led to the discovery of fundamental principles of heredity, like dominance, random segregation, and independent assortment.
Step-by-step explanation:
Parents pass on genes to their offspring, which are responsible for inherited traits such as purple flowers or sound seeds in pea plants. These genes contain alleles, which are different versions of a gene that determine specific traits. Gregor Mendel, an Austrian monk and scientist, conducted experiments with pea plants, establishing the foundational principles of heredity. His work demonstrated that each parent contributes one allele for each gene to their offspring. The combination of these alleles from the parents determines the traits the offspring will have.
Mendel's discoveries include the principles of dominance and recessiveness, as well as the concepts of random segregation and independent assortment. Some alleles are dominant, meaning they will express their trait if present, while others are recessive, meaning their trait will only be expressed if the individual has two copies of the recessive allele. By cross-pollinating pea plants with known traits, Mendel observed patterns of inheritance and determined these fundamental rules, predicated on the behavior of genes and alleles during reproduction.