Question

A wildflower native to California, the dwarf lupin (Lupinus nanus) normally bears blue lowers. Occasionally, plants with pink flowers are observed in wild populations. Flower color is controlled at a single locus, with the pink allele completely recessive to the blue allele. Harding (1970) counted several lupin populations in the California Coast Ranges. In one population of lupins at Spanish Flat, California, he found 25 pink flowers and 3291 blue flowers, for a total of 3316 flowers. Predict quantitatively the effect of natural selection on the frequencies of phenotypes in the next generation of lupins if the total number of flowers produced in the offspring is 3000 flowers.

Answer 1

Based on Mendelian Genetics and the rules of the Hardy-Weinberg Equilibrium, we can predict that the frequency of blue and pink flower alleles in the next generation of lupins will not change, given that natural selection, gene migration or mutation are not affecting these traits. The pink flowers, being homozygous recessive, help us calculate the allele frequencies.

Step-by-step explanation:

This question is asking for a prediction based on the rules of Mendelian Genetics. Since the pink flowering trait is recessive, it is represented by two identical alleles (pp). The blue flowering trait is dominant (could exist in BB or Bp forms). The pink flowers represent the homozygous recessive group (pp) and therefore can be used to calculate the allele frequency (q) in this population.

The frequency of q (allele for pink color) can be calculated by taking the square root of the number of pink flowers divided by the total number of flowers. This will give us q (frequency of allele for pink color). Knowing q, we can determine p, the frequency of the blue-allele, using the equation p=1-q

Therefore, the frequency of the blue allele (B) and pink allele (p) will not change in the next generation of lupins assuming that natural selection is not favoring any phenotype and other evolutionary forces like gene migration or mutation are not at play, given the rules of Hardy Weinberg Equilibrium.

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