Here's a breakdown:

* Gene: A segment of DNA that codes for a specific trait (like eye color, hair color, or height).

* Allele: A specific version of a gene. For example, there are multiple alleles for the gene that determines eye color, resulting in different eye colors.

* Heterozygous: Having two different alleles for a particular gene.

Example:

Let's say the gene for eye color has two alleles:

* B: Brown eyes (dominant)

* b: Blue eyes (recessive)

A person who is heterozygous for eye color would have one B allele and one b allele. They would likely have brown eyes since the brown allele is dominant.

Key Points:

* Heterozygosity allows for genetic diversity.

* The dominant allele is expressed in the phenotype (observable trait).

* The recessive allele is only expressed if two copies are present (homozygous recessive).

In contrast to heterozygous:

* Homozygous: Having two identical alleles for a particular gene (e.g., BB or bb).

Understanding heterozygosity is crucial for comprehending inheritance patterns and the diversity of traits within populations.