21.3: Chapter 3
( \newcommand{\kernel}{\mathrm{null}\,}\)
Multiple Choice
1. c
3. b
5. b
7. b
9. a
11. a
13. c
15. d
17. a
19. c
21. a
23. a
Fill in the Blank
1. neurotransmitters
3. locus coeruleus
5. calcium