Any substance that triggers an immune response is an antigen(s).
Answer:
One of these is natural selection, which is a process that increases the frequency of advantageous gene variants, called alleles, in a population. Natural selection can result in organisms that are more likely to survive and reproduce and may eventually lead to speciation.
Explanation:
Human bodies contain enzymes that can break down starch into glucose and use it for fuel. We do not have the enzymes necessary to breakdown cellulose.
