In this exercise, assume we're dealing with simple dominant/recessive relationships for two traits in a bean plant. The bean can have yellow or orange pods and can be inflated or constricted. Constricted or orange pods are novel (new) traits. You cross a true-breeding orange, constricted bean line with one that is true-breeding for yellow, inflated pods. The F1 seeds are planted and all grow up to bear fruit which are yellow and inflated. The F1 are allowed to self-fertilize.
You have several tasks:
- Design appropriate gene symbols.
- Use a branch diagram to show the expected phenotypic distribution of the F2 progeny.
- Of the F2 progeny, those with orange pods are selected and allowed to self. What is the expected phenotypic distribution among these select F3 progeny?
- Demonstrate the expected ratios of progeny from a test cross for the original F1 plants using a Punnett square.
Here's just the answer to 3: