nervous system

4. An organic catalyst.
8. Part of the brain that controls contious thoughts, controls the movement of every body part, and receives sensory messages from each body part.
10. sheath The insulating layer that covers a neurone.
11. glands Glands that produce hormones.
12. stem Part of the brain where the spinal cord enters the skull;it controls the body's vital functions, such as breathing, blood pressure and heart rate.
14. Part of the brain that is responsible for coordination and balance.
17. Muscles or glands that put the messages into effect.
19. The common name for the hormone epinephrine.
21. nervous system Part of the nervous system that slows the body down and controls it when it is resting.
24. impulse The ellectrical message carried by a nerve cell.
25. The organelle where proteins are manufactured.
26. All the chemical reactions occuring in the cells.
27. nerve the nerve that carries messages to the brain from the retina at the back of the eye.
28. cells The cells on which a hormone acts.

1. The chemical store of glucose i the liver and muscles.
2. Chemical substances that act as messengers in the body.
3. The space between two neutrons.
5. Any factor that stimulates a receptor and brings about a response.
6. A nerve fibre that sends nerve impulses away from the cell body.
7. nervous system The nerves that carry messages to and from he central nervous system and other parts of the baody.
8. nervous system(CNS) The brain and the spinal cord.
9. The process of maintaining a constant internal environment.
13. glands Endocrine gland situated on the kidneys.
15. Able to maintain a constant body temperature.
16. The lower half of the brain stem.
17. system All the endocrine glands of the body.
18. Special cell that detect stimuli.
20. A nerve cell.
22. body The part of the neurone that contains the nucleus.
23. actions Quick, automatic actions that protect the body from danger, they are also known as reflexes.