A fruit fly population has a gene with two alleles, A1 and A2. Tests show that 70% of the gametes produced in the population contain the A1 allele. If the population is in Hardy-Weinberg equilibrium, what proportion of the flies carry both A1 and A2?

A fruit fly population has a gene with two alleles, A1 and A2. Tests show that 70% of the gametes produced in the population contain the A1 allele. If the population is in Hardy-Weinberg equilibrium, what proportion of the flies carry both A1 and A2? 

A) 0.7
B) 0.49
C) 0.21
D) 0.42
E) 0.09



Answer: D

There are 40 individuals in population 1, all with genotype A1A1, and there are 25 individuals in population 2, all with genotype A2A2. Assume that these populations are located far from each other and that their environmental conditions are very similar. Based on the information given here, the observed genetic variation is most likely an example of

There are 40 individuals in population 1, all with genotype A1A1, and there are 25 individuals in population 2, all with genotype A2A2. Assume that these populations are located far from each other and that their environmental conditions are very similar. Based on the information given here, the observed genetic variation is most likely an example of 

A) genetic drift.
B) gene flow.
C) disruptive selection.
D) discrete variation.
E) directional selection.



Answer: A

If the nucleotide variability of a locus equals 0%, what is the gene variability and number of alleles at that locus?

If the nucleotide variability of a locus equals 0%, what is the gene variability and number of alleles at that locus? 

A) gene variability = 0%; number of alleles = 0
B) gene variability = 0%; number of alleles = 1
C) gene variability = 0%; number of alleles = 2
D) gene variability > 0%; number of alleles = 2
E) Without more information, gene variability and number of alleles cannot be determined.



Answer: B

Sparrows with average-sized wings survive severe storms better than those with longer or shorter wings, illustrating

Sparrows with average-sized wings survive severe storms better than those with longer or shorter wings, illustrating 

A) the bottleneck effect.
B) disruptive selection.
C) frequency-dependent selection.
D) neutral variation.
E) stabilizing selection.



Answer: E