Question

15. The gene for petal color in a flower has incomplete dominance, so that individuals with two Al alleles (AIAI) are red, individuals with two A2 alleles (A2A2) are white, and individuals with one of each allele (A1A2) are pink. In a cross between a red flower and a white flower, what is the probability of getting a pink offspring? (2 points) In a cross between a red flower and a pink flower, what is the probability of getting a pink offspring? (2 points) In a cross between two pink flowers, if there are two offspring, what is the probability of getting one red offspring and one pink offspring? (2 points) In a cross between two pink flowers, if there are two offspring, what is the probability of getting one red offspring and one white offspring? (2 points) In a cross between two pink flowers, if there are nine offspring, what is the probability of getting exactly three pink offspring? (2 points)

Answer 1

15) a. A1A1. X A2A2

I

A1A2. 100% will be pink A1A2

b. A1A1. X A1A2

I

A1A1. A1A2 50% pink and 50% red

c. A1A2. X A1A2

I

A1A1. A1A2. A2A1. A2A2. Red 1/4, pink 1/2, white 1/4

Probabilty of one red and another pink or one pink and another red

1/4x1/2 + 1/2x1/4= 1/4 =25%

D) probabilty of first one is red and second one white or first one is white another one red

1/4x1/4+1/4x1/4= 1/8

E) probabilty of all three pink flower= 1/2x1/2x1/2= 1/8

Hope it's clear.thanks