Answer;
Gene flow
Gene flow is the most important factor that holds a gene pool of a species together and prevents speciation.
Explanation;
-Evolution may occur as a result of genes being transferred from one population to another. This gene flow occurs when there is migration. The loss or addition of people can easily change gene pool frequencies even if there are no other evolutionary mechanisms operating.
-Gene flow may also occur without migration, for instance, when people travel to another area and successfully mate with people in the population there, a transfer of genes occurs between the populations even though the traveler returns home.
-Additionally, gene flow may flow between species. A good example is when segments of DNA are transferred from one species to another by viruses as they invade the cells of animals or plants.
The answer is c) a number and a unit
Answer:
B
Explanation:
An object at rest will stay at rest unless acted on by an unbalanced force and an object in motion will stay in motion unless acted on by an unbalanced force.
eg. Arrow in space with no gravity will go forever because of the lack of gravity and no air resistance but the opposite is true on Earth.
Gene linkage is the exception from Mendel's low of independent assortment, because during meiosis these genes travel together.
