Suppose a population is carrying a condition controlled by two alleles: r (dominant) and r (recessive). only homozygous individuals that have two copies of the recessive allele have the condition. if the r allele is found in 15 percent of the population, what's the frequency of the rr genotype?
a. 72.25 percent
b. 12.75 percent
c. 25.5 percent
d. 2.25 percent

The answer is A. 72.25 percent.

The Hardy-Weinberg principle can be used:

p² + 2pq + q² = 1 and p + q = 1

where p and q are the frequencies of the alleles, and p², q² and 2pq are the frequencies of the genotypes.

The r allele (q) is found in 15% of the population:
q = 15% = 15/100
Thus, q = 0.15

To calculate the R allele frequency (p), the formula p + q = 1 is used:
If p + q = 1, then p = 1 - q
p = 1 - 0.15
Thus, p = 0.85

Knowing the frequency of the R allele (p), it is easy to determine the frequency of the RR genotype (p²):
p² = 0.85² = 0.7225

Expressed in percentage, p² = 72.25%.

answer: tributaries flow into rivers.

wetland is a biome that develops when the water gets accumulated in a land exhibiting a huge depression. these form either seasonally or permanently. the water in the wetland comes from rivers, lakes, ocean, flood, rain or other sources. the wetlands includes mangroves, marshes and peatland.

tributaries flow into the rivers develops a wetland because such water will get deposited in the depression and will restrict the original flow of tributary water. hence, water with low drainage current combines with the river water.

i believe it would cause an increase of percipitation, though i could be wrong. so i would say b is the answer.