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In a particular species of frogs, black spots are a dominant trait and their absence is a recessive trait. In a population of frogs, 50 are homozygous for the dominant trait, 34 are heterozygous dominant, and 16 show the recessive trait. Which expression is the correct way to calculate the frequency of the dominant allele?

A. [tex]\frac{50}{100}[/tex]
B. [tex]\frac{84}{100}[/tex]
C. [tex]\frac{50}{200}[/tex]
D. [tex]\frac{134}{200}[/tex]
E. [tex]\frac{100}{200}[/tex]



Answer :

GinnyAnswer
To determine the correct way to calculate the frequency of the dominant allele in this population of frogs, follow these steps:

1. Count the total number of frogs:
- Homozygous dominant: 50
- Heterozygous dominant: 34
- Recessive: 16
- Total frogs = 50 + 34 + 16 = 100

2. Calculate the number of dominant alleles:
- Homozygous dominant frogs contribute two dominant alleles each. Therefore, for 50 homozygous dominant frogs: [tex]\(50 \times 2 = 100\)[/tex] dominant alleles.
- Heterozygous dominant frogs contribute one dominant allele each. Therefore, for 34 heterozygous dominant frogs: [tex]\(34 \times 1 = 34\)[/tex] dominant alleles.
- Total dominant alleles = 100 + 34 = 134

3. Calculate the total number of alleles in the population:
- Each frog has two alleles. Therefore, for 100 frogs: [tex]\(100 \times 2 = 200\)[/tex] alleles.

4. Calculate the frequency of the dominant allele:
- The frequency of the dominant allele is the ratio of the total number of dominant alleles to the total number of alleles.
- Therefore, the frequency of the dominant allele is [tex]\(\frac{134}{200}\)[/tex].

Given these calculations, the correct answer is:

D. [tex]\(\frac{134}{200}\)[/tex]