One gene copy from each parent

Every living thing gets one copy of each gene from each parent, so it has two versions of every trait. When the two versions are different, the dominant one shows and the recessive one stays hidden, but it can still be passed on.

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In the picture

Parent plant with purple flowers: it carries two purple versions of the flower-color gene.
Parent plant with white flowers: it carries two white versions of that gene.
The offspring gets one version from each parent, one purple and one white.
The offspring has purple flowers because the purple version is dominant and hides the white one.

Examples

Two black Labrador dogs can have a yellow puppy if both carry a hidden version of the gene for yellow.
A child can have curly hair like their mother and a nose shape like their father.

Key takeaways

Each parent passes on only one of its two versions of a gene.
A dominant version hides a recessive one, but the recessive version still gets passed on.