Genetic crosses help us understand how traits are passed down from parents to their kids. This is especially important for figuring out dominant and recessive traits. Here are some key ideas to know:

1. Phenotypes vs. Genotypes:

   • Phenotype: This is how a trait looks, like flower color.
   • Genotype: This is the genetic code, like BB, Bb, or bb.

2. Mendelian Inheritance:

   • In pea plants, the strong trait for purple flowers (P) hides the weaker trait for white flowers (p).
   • When we breed two pure plants (PP and pp), all the kids (F1 generation) will have purple flowers. That’s 100% purple!

3. Punnett Squares:

   • These are tools that help us predict the traits of the offspring.
   • For example, if we cross two plants with the genotype Pp (both having one purple and one white trait):
     • The ratio of their gene combinations will be 1:2:1 (PP, Pp, pp).
     • The ratio of how they appear will be 3:1 (3 purple flowers to 1 white flower).

4. Statistics:

   • In a typical cross with one trait, about 75% of the offspring show the dominant trait. This helps us see how traits are inherited.