Here's a breakdown:

* Gene: A segment of DNA that contains the instructions for building a specific protein.

* Allele: A specific variant of a gene. Think of it like different flavors of the same ice cream. You could have "chocolate" and "vanilla" alleles for the "ice cream" gene.

Example:

Let's consider the gene for eye color. There are different alleles for this gene, such as:

* Brown eye allele: This allele codes for the production of a pigment that makes eyes brown.

* Blue eye allele: This allele codes for the production of less pigment, resulting in blue eyes.

A person inherits two alleles for each gene, one from each parent. This combination of alleles determines their traits.

Key Concepts:

* Homozygous: Having two identical alleles for a gene (e.g., two brown eye alleles).

* Heterozygous: Having two different alleles for a gene (e.g., one brown eye allele and one blue eye allele).

Let me know if you have any more questions!