day 9 vocab

3. a signal transmitted along a nerve fiber. It consists of a wave of electrical depolarization that reverses the potential difference across the nerve cell membranes.
5. the fundamental units of the brain and nervous system
7. an organ or cell able to respond to light, heat, or other external stimulus and transmit a signal to a sensory nerve.
9. a short branched extension of a nerve cell, along which impulses received from other cells at synapses are transmitted to the cell body.
10. a space that separates two neurons
11. treatment with a vaccine to produce immunity against a disease; inoculation.
13. a small colorless disk-shaped cell fragment without a nucleus, found in large numbers in blood and involved in clotting.
14. bacterium, virus, or other microorganism that can cause disease.
15. the nerve pathway involved in a reflex action, including at its simplest a sensory nerve and a motor nerve with a synapse between
17. a blood protein produced in response to and counteracting a specific antigen. Antibodies combine chemically with substances which the body recognizes as alien, such as bacteria, viruses, and foreign substances in the blood.

1. a junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter.
2. a chemical substance that is released at the end of a nerve fiber by the arrival of a nerve impulse
4. the ability of an organism to resist a particular infection or toxin by the action of specific antibodies or sensitized white blood cells.
6. a large phagocytic cell found in stationary form in the tissues or as a mobile white blood cell, especially at sites of infection.
8. an organ or cell that acts in response to a stimulus.
12. a toxin or other foreign substance which induces an immune response in the body, especially the production of antibodies.
16. a colorless cell that circulates in the blood and body fluids and is involved in counteracting foreign substances and disease