Question

1. Discuss how an action potential is propagated along an axon,including all relevant molecules and
processes. Be sure to discuss how resting membrane potential isrestored. How is the signal transmitted to
the next neuron?

2. Explain the process of contraction in a skeletal muscle,starting with how the signal enters a muscle cell at
the neuromuscular junction. Include all relevant ions, structures,and processes in your explanation.

3. Using your knowledge of both animal behavior and evolution,define and explain altruistic behavior. Under
what sorts of circumstances would we expect to see altruisticbehavior, and why? Under what sorts of
circumstances would we expect natural selection to favor allelesassociated with behaving altruistically?

4. Use your understanding of population ecology to describe andexplain the global human population over
the last one or two thousand years. What can you predict for thefuture of the global human population, and
why? (Your predictions should be based on population ecology!) Whatpolicy changes, if any, do you think
are advisable given the predictions you have made?

5. Define symbiosis and explain the major categories ofsymbiotic interactions, including how each type of
interaction may be shaped by natural selection. To support yourexplanation, give at least two examples of
type of symbiosis, explaining how each species is affected (e.g.,helped, harmed, or unaffected) and why.

6. Describe the flow of energy in an ecosystem. Where does theenergy initially come from? Why isn