[Campbell Biology P.327] Consider a trihybrid cross between two pea plants: PpYyRr x Ppyyrr.... | Practice Question

Consider a trihybrid cross between two pea plants: PpYyRr x Ppyyrr. What is the probability of an offspring having the genotype ppYyrr?

  • A: 1/4
  • B: 1/8
  • C: 1/16
  • D: 1/32

Explanation

We calculate the probability for each gene pair independently: Prob pp from Pp x Pp is 1/4. Prob Yy from Yy x yy is 1/2. Prob rr from Rr x rr is 1/2. Using the multiplication rule, the final probability is 1/4 1/2 1/2 = 1/16. This exact calculation is shown in the text.