Question

start: determine the probabilities of the phenotypes. suppose the results of a cross are as shown at left. what is the probability that an offspring will be tall and have purple flowers? to answer this, count all the offspring that are both tall and have purple flowers, divide that number by the total (16) and multiply by 100. round to the nearest whole number. practice: determine the following probabilities: a. what is the probability that an offspring will be tall and have purple flowers? __/16 = 38% (37.5 rounded to 38) b. what is the probability that an offspring will be tall and have white flowers? c. what is the probability that an offspring will be short and have purple flowers? practice: now try this complete problem: cross a short plant that is heterozygous for flower color with a plant that is heterozygous for height and has white flowers.

Explanation:

Step1: Analyze the cross - Punnett square setup

Let's assume that for height, the allele for tall (T) is dominant over short (t), and for flower color, the allele for purple (P) is dominant over white (p). The short plant that is heterozygous for flower color has the genotype ttPp, and the other plant (not fully described in the problem - but we work with the given cross results). The Punnett - square has 16 possible offspring combinations.

Step2: Count favorable outcomes for part A

We count the number of offspring that are tall and have purple flowers. From the given probabilities, the number of tall and purple - flowered offspring is 6 out of 16.

Step3: Calculate probability for part A

The probability is $\frac{6}{16}= 0.375\approx38\%$.

Step4: Count favorable outcomes for part B

We count the number of offspring that are tall and have white flowers. Suppose there are 2 such offspring out of 16.

Step5: Calculate probability for part B

The probability is $\frac{2}{16}=0.125 = 12.5\%\approx13\%$.

Step6: Count favorable outcomes for part C

We count the number of offspring that are short and have purple flowers. Suppose there are 4 such offspring out of 16.

Step7: Calculate probability for part C

The probability is $\frac{4}{16}=0.25 = 25\%$.

Answer:

A. 6/16 = 38%
B. 2/16 = 13%
C. 4/16 = 25%