What defines the F1 generation?

The F1 generation, short for "first filial generation," is defined as the direct offspring produced from the crossbreeding of the parental generation, known as the P generation. In genetics, when two genetically distinct parents breed, their offspring represent the first generation in this sequence. The F1 generation typically exhibits traits that are a combination of the characteristics of the parent organisms, often showcasing dominant traits if one parent contributes dominant alleles.

The other options do not accurately define the F1 generation. The next generation after F2 would refer to subsequent generations beyond F1 and is therefore not applicable. The P generation specifically denotes the original parent organisms, which precede the F1. Lastly, while organisms with different alleles for a trait can exist, this description does not specifically pertain to the definition of the F1 generation itself, but rather relates to genetic variation in general.