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.
It depends on which virus you are referring to specifically. Viruses come in many shapes and types; their variations are tremendous.
For HIV and Influenza, viruses acquire their envelops after maturation, during the budding off or detachment stage from the host cell.
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The reduction in chromosome number occurs during <u>meiosis I.</u>
Chromosomes are long molecules of DNA that contain some or all of an organism's genetic material. In most chromosomes, very long, thin strands of DNA are coated with packaging proteins. In eukaryotic cells, the histones are the most important of these proteins.
Within the nucleus of all cells, DNA molecules are packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly wrapped many times around proteins called histones that support its structure.
Another type of cell division, meiosis, ensures that humans have the same number of chromosomes from generation to generation. This is a two-step process in which the number of chromosomes is halved from 46 to 23 to form sperm and eggs.
Learn more about chromosomes here:-brainly.com/question/11912112
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