Across
- 2. system that increases the production of hormones
- 4. special structures that detect stimuli
- 6. nerve cell
- 7. consists of organs and tissues that release chemical messages
- 9. a quick automatic response to a stimulus
- 10. made up of the brain and spinal cord
- 14. space between neurons
- 15. structure of neurons protected by vertebrae
- 16. controls muscle movement and regulates balance
- 17. tympanic membrane
- 18. gathers, processes, and responds to the environment
- 19. causes a response
- 20. reaction to a stimulus
- 21. receptors that detect colors
Down
- 1. carried in bloodstream and produced by glands
- 2. contains sensory and motor neurons
- 3. controls involuntary functions
- 5. area of the eye that detects light
- 8. controls memory, language, and thought
- 11. receptors that detect light
- 12. system that decreases the production of hormones
- 13. detects or senses the environment