a) Gene: It is the shortest segment of DNA that determine a biological character of an organism.

b) Allele: It is one of a no. of alternative forms of the same gene responsible for determining contrasting character.

c) Locus: The point on a chromosome where an allele is located is called locus.

d) Homozygous: A diploid individual carrying two identical alleles is called homozygous.

e) Heterozygous : A diploid individual that carry two different allele is called heterozygous.

f) Genotype: A genotype is the genetic expression of an organism.

g) Phenotype: It is the physical expression of an organism.

h) Hybrid : It is the product formed by two pair of contrasting character fused to give a single character.

i) Hybridization: The process of formation of hybrid by crossing two pair of contrasting character is called hybridization.