Here's why:

* F1 generation: This refers to the offspring produced by crossing two parent organisms (the parental generation, or P generation).

* Dominant trait: A dominant trait is one that will be expressed in the offspring even if only one copy of the gene for that trait is present.

Example:

* Let's say you have a plant with purple flowers (dominant trait) and another with white flowers (recessive trait).

* If you cross these two plants, the F1 generation will all have purple flowers. This is because the purple flower gene is dominant, so even though the offspring inherit one gene for purple flowers and one for white flowers, the purple flower gene is the one expressed.