Question

33 using mendels flower color (purple is dominant, white is recessive), if two heterozygous plants are crossed, what is the probability that the first two - offspring will have purple flowers? multiple choice 9/16 6/4 1/2 1/16

Explanation:

Step1: Determine the genotypes of parents

Let the dominant allele for purple be \(P\) and the recessive allele for white be \(p\). Heterozygous plants have the genotype \(Pp\).

Step2: Set up the Punnett - square

When \(Pp\times Pp\) is crossed, the Punnett - square has the following combinations: \(PP : Pp:pp = 1:2:1\). The probability of a plant having purple flowers (genotypes \(PP\) or \(Pp\)) is \(\frac{3}{4}\) since \(P\) is dominant over \(p\).

Step3: Use the multiplication rule for independent events

Since the events of the first - offspring having purple flowers and the second - offspring having purple flowers are independent, we multiply the probabilities. The probability that the first offspring has purple flowers is \(\frac{3}{4}\), and the probability that the second offspring has purple flowers is also \(\frac{3}{4}\). So the probability that both have purple flowers is \(\frac{3}{4}\times\frac{3}{4}=\frac{9}{16}\).

Answer:

A. \(\frac{9}{16}\)