1) B
(I'm not so sure of this one) All of the other options have a steady impact on population regardless of the density of organisms except competition
2) D
Increased carbon dioxide levels would not hinder plant growth, and tsunamis aren't really linked to carbon dioxide levels. Increased carbon dioxide is unlikely to lower the air temperature so only D is left.
3) A
4) Three properties of water that allow it to sustain life are that it is adhesive, it is a good solvent, and cohesion. Adhesion is important in situations such as water travelling up xylem tubes in plants so that the water is not pulled down by gravity and can reach parts of the plant that need water. Cohesion allows the water being pulled up the xylem to stay together and for water molecules to be pulled when a neighbouring one is moved. Water being a good solvent allows inorganic minerals to be taken with water through vascular tissue, such as in the previous example.
Answer:
Because it is only possible to be 100% sure that two species are closely related, in genetic terms, when the DNAs of these species can be analyzed. This analysis is only possible through molecular tests.
Explanation:
Molecular tests are bikini techniques that can analyze species at the molecular level, more specifically, these tests can deeply analyze the DNA (or RNA and proteins) of a species giving precise results on the molecule and allowing scientists to study it deep.
In studies, where the scientist wants to know how the species are genetically related, it is common for molecular tests to be introduced, as a way for the scientist to be 100% sure of the relationship between the species.
Darwin noticed that there were different kinds of the same species. For example, he studied four different kinds of finches. Each one had a different beak and are different kinds of food. This was the first time genetic diversity had been so obvious to humans.
Answer:
The eukaryotes, bacteria, and archaea that live in and on the human body are called normal microbiota. When they were originally discovered, scientists thought that the relationship between these organisms was parasitic because they thought that the organisms benefit from living on the host but did not help the host. In recent years, researchers have determined that most of our resident microbes derive and give benefit to the host. This makes the relationship between host and microbe one of mutualism. Pathogenic, on the other hand, are microbes that cause diseases.
