Antibodies, also called immunoglobulins, are proteins manufactured by the body that help fight against foreign substances called antigens. When an antigen enters the body, it stimulates the immune system to produce antibodies. (The immune system is the body's natural defense system.) The antibodies attach, or bind, themselves to the antigen and inactivate it.<span>
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Answer:
O founder's effect
Explanation:
A founder effect can be defined as the loss of genetic variation when a new population is established from a few individuals. This process is known to increase the frequency of particular gene variants (alleles) at different <em>loci</em> when they are selectively neutral (or nearly neutral), and thereby such genes are fixed by genetic drift (i.e., through the random sampling of founder individuals). Interestingly, it has been discovered that the majority of South American and Central American Indians are nearly exclusively in the O blood group, which has been further associated with random genetic drift and a founder effect.
Natural selection is the process that result in the adaptation of an organism to environment by means of selectively reproducing changes in its genotype, or genetic constitution. It is the a key mechanism of evolution. Charles Darwin popularised the term "natural selection" contrasting it with artificial selection, which is intentional, whereas natural selection is not.
To make it simple, let's have a group of beetle composing of green and some are brown as an example. here, there is a variation in traits. Since the environment could not support continuous population growth, not all species can reproduce to their full potential. Green beetles can easily be eaten by other species like birds compared to brown beetles. The surviving brown beetles will then generate brown offsprings because their trait has a genetic basis. Since more brown beetles survive and becomes more common in the population, the process continues until all individuals will eventually be brown. so basically, if you have variation, differential reproduction, and heredity, you will have evolution by natural selection as an outcome.
If a person is "sterile", this means that they cannot reproduce. The word "sterilized" is essentially stating that there is no productive activity in order to be able to reproduce.
