2. In your own words, describe the anatomy of the central nervous system, the peripheral
nervous system, and the endocrine system. How do these three systems work together to
affect a person's development and behavior?
3. "It's going to be amazing when humans go to Mars," a classmate says. "People will be able
to see and hear and feel everything. There will be no limits!" Explain to the classmate what
humans can sense and perceive and what they aren't able to sense and perceive. Give at
least three examples of each. Use the term "absolute threshold" in your answer.
4. "I've been afraid of heights my whole life, and that's never going to change," a relative says.
"That is just how my brain is wired." Explain to this relative what neuroplasticity means (in
your own words) and how it affects humans.
5. "Why do people have to go to sleep?" asks a seven-year-old as their parent puts them to
bed. In terms that a young child would understand, explain at least two of the reasons
scientists have suggested that humans need sleep.