Genes that prevent other genes from showing their traits are called recessive genes.

Here's a breakdown:

* Alleles: Different versions of the same gene are called alleles.

* Dominant Allele: A dominant allele will always express its trait, even if there is only one copy of it present.

* Recessive Allele: A recessive allele will only express its trait if two copies of the allele are present.

Example:

Let's say there's a gene for eye color with two alleles:

* B: Brown eyes (dominant)

* b: Blue eyes (recessive)

* BB: Brown eyes (dominant)

* Bb: Brown eyes (dominant)

* bb: Blue eyes (recessive)

In this case, someone with at least one "B" allele will have brown eyes. Only someone with two "b" alleles will have blue eyes.