The break down of carbon based molecules into smaller molecules
B. Being new to the country, it is safer for Sarah to take precautions until she gets acclimated
I believe this is the answer as the other answers take too many assumptions as the question doesn't explicitely state that Sarah has skin problems.
Genotypes of the dog color are:
BB dominant homozygous-brown phenotype
bb recessive homozygous-white phenotype
Bb heterozygous-tan phenotype
Cross between brown and pan dog would be:
P: BB x Bb
F1: BB Bb BB Bb
The ratio would be 1:1 (brown dog:pan dog).
Answer;
-Allele frequency change
In single-gene traits, natural selection can lead to allele frequency change.
Explanation;
-Allele frequencies can change over time within a single population, and frequently differ between populations. This change is due to four different processes: mutation, selection (natural and artificial), gene flow and genetic drift.
-Random forces lead to genetic drift. Sometimes, there can be random fluctuations in the numbers of alleles in a population. These changes in relative allele frequency, called genetic drift, can either increase or decrease by chance over time.
