Description 1

Correct!

Dr. Foster: ‘Great job with identifying that description for homozygotes and heterozygotes. Now let’s talk about how traits pass from parents to offspring. Mendel was an Austrian scientist who performed cross-pollinations between pea flowers. His work laid the foundation for our modern understanding of genetics.’

[One of your classmates sets down a tray of prepared samples.]

Alice: ‘So, in Mendel’s experiment, he took a purple pea flower and a white pea flower, then tracked the traits in the first (F1) generation and the second (F2) generation. The F1 were all purple, but the F2 split into a 3:1 ratio, mostly purple with some white.’

Dr. Foster: ‘Exactly. He wondered what happened to the white trait in the first generation, and discovered it reappeared in the second generation. We call that trait recessive, and the one that shows up whenever it’s present is the dominant trait. Given that only a small portion of the F2 were white, which flower color do you think is dominant in Mendel’s experiment?’

Which pea flower color is the dominant?