Law of segregation - During gamete formation the genes of a particular character separate and enter different gametes. This is the law of segregation. This law is also called law of purity of gametes.
Example: During gamete formation the paired factors (Tt) present in the F1 plant segregate independently and enter different gametes. So each gamete receives either T or t from the paired factors Tt, which are responsible for the expression of a single character.
Law of independent assortment - This law is based on dihybrid experiment. According to this law, the genes for each pair of characters separate independently from those of other characters during gamete formation.
Example: Consider a plant with yellow round (YYRR) seeds being crossed with another pea plant with green wrinkled (yyrr) seeds. During gamete formation of a dihybrid cross, the factors for yellow colour assort out independently of the factors for round shape.The gene Y may combine with the dominant gene R or the recessive gene r of the other character and enter a gamete. In the same way, the gene y may combine with the dominant gene R or the recessive gene r and enter another gamete. So the F1 dihybrid plants produce four types of gametes and they are YR, Yr, yR and yr.