The Concept of Gene Flow Indicates That Evolution of Populations

question 40

Essay

The concept of gene flow indicates that evolution of populations can occur when individuals enter or leave a population. The addition of new alleles into the population makes it easy to visualize changes to phenotypes. Explain how emigration can lead to evolutionary change.

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Definitions:

All-or-none Law

The principle that the strength of a response of a nerve or muscle fiber is not dependent on the strength of the stimulus; if a stimulus is above a certain threshold, a nerve or muscle fiber will fire.

Action Potential

A brief electrical charge that travels down an axon, generating a nerve impulse as a response to a stimulus.

Stimulus

Any occurrence or circumstance that prompts a reaction from a living being.

Acetylcholine

A neurotransmitter in both the peripheral nervous system (PNS) and central nervous system (CNS) in many organisms including humans.