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1. HELP one quick biology question!!!
1) In a population's gene pool, two alleles exist for a trait. C, the dominant allele, constitutes 60% of the gene pool. Homozygous dominant individuals constitute what percentage of the population?
A. 0.6% C. 36%
B. 52% D. 24%

2) What proportion of the gametes in this population contain gene c?
A. 0.16% C. 40%
B. 24% D. 48%

I know that number 1 is C- 36%, but I'm having alot of trouble trying to figure out number two! If someone could show me how to do it step by step, that would be amazing !!
2. Re: HELP one quick biology question!!!
(Original post by Keedeon)
1) In a population's gene pool, two alleles exist for a trait. C, the dominant allele, constitutes 60% of the gene pool. Homozygous dominant individuals constitute what percentage of the population?
A. 0.6% C. 36%
B. 52% D. 24%

2) What proportion of the gametes in this population contain gene c?
A. 0.16% C. 40%
B. 24% D. 48%

I know that number 1 is C- 36%, but I'm having alot of trouble trying to figure out number two! If someone could show me how to do it step by step, that would be amazing !!
You sure the potential answers to the second question are right? If gene C makes up 60% of the gene pool, surely the proportion of gametes with allele C would be >50%? I've tried to do the question a few times, and get an answer of 84% each time. Maybe answer D is a typo?
3. Re: HELP one quick biology question!!!
(Original post by Kidneyjean)
You sure the potential answers to the second question are right? If gene C makes up 60% of the gene pool, surely the proportion of gametes with allele C would be >50%? I've tried to do the question a few times, and get an answer of 84% each time. Maybe answer D is a typo?

I'm sure that the potential answers to the second question are right, yeah... :/
4. Re: HELP one quick biology question!!!
(Original post by Keedeon)
1) In a population's gene pool, two alleles exist for a trait. C, the dominant allele, constitutes 60% of the gene pool.

Homozygous dominant individuals constitute what percentage of the population?
A. 0.6% C. 36%
B. 52% D. 24%

2) What proportion of the gametes in this population contain gene c?
A. 0.16% C. 40%
B. 24% D. 48%

I know that number 1 is C- 36%, but I'm having alot of trouble trying to figure out number two! If someone could show me how to do it step by step, that would be amazing !!
Hi.

Unless I'm being stupid here, I'm pretty sure that the answer is C, 40%.

The recessive allele, c, is 40% of the population; because gametes have a random assortment of genes, the proportion of alleles in gametes is the same as proportion in the population.

Alternatively, you can say that the homozygous recessives make up 0.4x0.4=16% of the population, and the heterozygotes make up 0.4x0.6x2=48% of the population. All of the gametes produced by the homozygous recessives would contain the c gene, and half of the gametes produced by the heterozygotes would contain c.

Therefore, 16+(48/2)=40
Last edited by Tpx; 04-06-2012 at 20:45.
5. Re: HELP one quick biology question!!!
Do you know how to solve for this question, I have no idea, I think the answer is 60%, but I'm not sure..

Sixty-four percent of a population is able to taste a chemical called PTC. Tasters are either homozygous dominant or heterozygous for the trait.

1. Calculate the percentage of the population that carries the recessive allele