Question

A botanist crosses two pink-flowered plants. The cross involves alleles that were not clearly dominant or recessive and could make red, pink, and white-flowered plants. If four plants are produced from the cross, what is the expected number of white-flowered plants?

Answer 1

In this cross involving alleles for red, pink, and white-flowered plants, the expected number of white-flowered plants can be determined using Punnett squares. The expected number of white-flowered plants is 1 out of 4 plants.

Step-by-step explanation:

In this cross involving alleles for red, pink, and white-flowered plants, the expected number of white-flowered plants can be determined using Punnett squares. Since none of the alleles are clearly dominant or recessive, we can consider all possible combinations of the alleles in the offspring. There are 6 possible genotypes that can produce a white-flowered plant: WW, RW, WR, RRW, RWR, and WRR. Out of these 6 genotypes, 1 genotype (WW) will produce a white-flowered plant. Therefore, the expected number of white-flowered plants is 1 out of 4 plants.

Answer 2

1

Step-by-step explanation:

According to the information in this question, a gene coding for flower color in a plant is involved. The allele for red color (R) is incompletely dominant over the allele for white color (r) to form an intermediate phenotype/color i.e. Pink that is heterozygous (Rr) for the gene.

If two pink plants are crossed i.e. Rr × Rr, each parent will produce R and r gametes. Using these gametes in a punnet square (see attached image), the following offsprings will result: RR, Rr, Rr, and rr.

Out of these four offsprings;

1 RR is red : 2 Rr is pink: 1 rr is white

Hence, If four plants are produced from this cross, according to this question, the expected number of white-flowered plants will be 1 out of 4.