<span>It is the variable in an experiment is not directly altered</span>
Answer:
I think the answer is A.
Explanation:
Ponds and lakes are both inland bodies of freshwater that contain living creatures. Lakes are normally much deeper than ponds and have a larger surface area. ... All the water in a pond is in the photic zone, meaning ponds are shallow enough to allow sunlight to reach the bottom.
The yearly process known as thermal stratification. A pond that is thermally stratified simply means that there is a noticeable temperature gradient as the water gets deeper. You may have noticed this in summer while swimming.
Catalase.is an enzyme in the liver that breaks down harmful hydrogen peroxide into oxygen and water.
Dominant' traits will actually disappear faster if they are disadvantageous.
Think about it: if everyone who has even a single copy of a particular allele is at a disadvantage (manifests the phenotype, in this case six fingers), then even single copies are selected against.
In the case of recessive traits, selection occurs only against homozygous carriers, who may be very rare if the allele itself is rare.
A concrete example would be something like Tay-Sachs disease. If the allele that causes this were dominant, every carrier would die before adulthood, and it would occur only as a very rare de novo mutation. But because it is recessive, it persists for now; heterozygous carriers have no disadvantage.
