They will always produce round seeds. They will only produce wrinkled seeds. Each offspring plant will have some round and some wrinkled seeds. Unless the plant with wrinkled seeds was pure recessive, no prediction can be made.
I gave my students this multiple choice question: In pea plants, the trait for round seeds is dominant over the trait for wrinkled seeds. If a pure dominant plant with round seeds is crossed with a plant with wrinkled seeds, what can be predicted about the offspring plants?

Only one answer is correct among these 4 choices:
- They will always produce round seeds.
- They will only produce wrinkled seeds.
- Each offspring plant will have some round and some wrinkled seeds.
- Unless the plant with wrinkled seeds was pure recessive, no prediction can be made.

Could you tell me which one is correct?

They will always produce round seeds.