I think the correct answers from the choices listed above are options B and C. The two main sources that lead to increased genetic variation would be Gamete mutations and recombination. <span>Gametes mutations leads to change in DNA information, recombination allows mixture of genotypes.</span>
Answer: No
Explanation: Exotic and invasive species are two types of non-native species, which are introduced to ecosystems by natural processes or humans. Most exotic species are domestic, and they do not harm ecosystems. But, invasive species are harmful to the ecosystems.
Answer:
Amoeba reproduces asexually through binary fission. In this process, an individual divides itself into two daughter cells. These are genetically identical to each other.
Answer:
<em>This is an example of natural selection (adaptation).</em>
Explanation:
Natural selection tends to favor those organisms which are better adapted to live in an environment.
As tortoises having flat shell and long neck were better adapted to live in barren area, hence through natural selection those organisms were favored in such an ecosystem.
As tortoises that lived on the vegetative lands were more adapted to live in such an ecosystem, hence through natural ecosystem these organisms were favored and increased in numbers.
The correct answer is A.
Toxins and various pollutants increase in concentration through the food chain in a process called biomagnification. This means that the organisms on the top of the food chain, like the herring gull, have many times greater concentration of toxins than the lower food chain level organisms because they prey on lower food chain level organisms. If a herring gull ears 100 herrings, it will have a 100x times greater concentration of toxins in its body than a herring.
