gene

A gene is a segment of DNA that contains information about a certain trait.

• Each gene describes how to make a certain protein.

• Genes are passed from parents to offspring and contain the information needed to specify traits.

• Genes are arranged, one after another, on structures called chromosomes.

• Only a portion of the single long DNA molecule in a chromosome corresponds to a single gene.

• Humans have approximately 20,000 genes arranged on their chromosomes!