Final answer:
The multiplication rule in genetics is used to calculate the probability of two independent genetic traits occurring together by multiplying individual probabilities, while the addition rule is used to calculate the probability of one of several traits occurring by adding individual probabilities, subtracting overlap if necessary.
Step-by-step explanation:
The student has asked about the multiplication rule and addition rule in the context of genetics. These are two foundational concepts used to calculate the probabilities of inheriting different genetic traits. The multiplication rule, symbolized as P(A AND B) = P(A|B)P(B), is used when you want to find the probability of two independent events occurring together. For example, if you are determining the probability that offspring will inherit two specific traits (e.g., round seeds and yellow color), you would multiply the probability of each event occurring separately.
In contrast, the addition rule is symbolized as P(A OR B) = P(A) + P(B) − P(A AND B) and is used when calculating the probability of one of several events occurring. If you want to know the probability of offspring having either one trait or another (e.g., round seeds or wrinkled seeds), you add the probabilities of the individual events, subtracting the probability of them occurring together if necessary. These rules are essential for predicting trait inheritance in various genetic crosses.