Answer:
See the answer below
Step-by-step explanation:
A gene is made up of a pair of alleles that can be the same or different. When a gene is made up of the same allele, such gene is said to be homzygous and an individual is said to be true-breeding for that gene. When a gene is made of different alleles, such a gene is said to be heterozygous.
An allele, on the other hand, represents the alternate form of a gene. For example, height can be tall or short. Tallness represents one allele while shortness represents another allele. When the two alleles for a height are tall or short, it is homzygous, when it consists of one tall and one short allele, it is heterozygous.