| A | B |
|---|
| the main functions [jobs] of the nervous system | takes in information from the environment, stores memories, controls actions, directs the bodies responses |
| reaction time | time it takes for a nerve impulse to make its way through the nervous system |
| nerve impulse | message carried through the body by nerve cells |
| neurons | nerve cells |
| sensory neurons | neurons that pick up signals from the environment |
| stimulus | signal from the environment |
| motor neurons | neurons that cause muscles to move in reaction to a stimulus |
| brain | control center of the nervous system |
| skull | protective covering of the brain |
| three main parts of the brain | cerebrum, cerebellum, medulla |
| cerebrum | largest part of the brain |
| cortex | outer layer of the cerebrum |
| functions [jobs] of the cerebrum | thinking, memory storage, decision making, and the beginnings of emotions and attitudes start in this part of the brain |
| right half of cerebrum | controls left half of body |
| left half of cerebrum | controls right half of body |
| cerebellum | second largest part of the brain |
| functions of the cerebellum | coordinates muscles of the body, where our sense of balance comes from |
| medulla | connects brain to the spinal column |
| function [job] of the medulla | this part of the brain controls the involuntary actions of the body |
| involuntary actions | actions that you don't think about |
| nerves | pathways that connect the brain to all parts of the body |
| senses | these nerve impulses let you collect information from the environment and send it to the brain which decides a proper action |
| sense receptors | special sensory neurons that receive stimuli from the environment |
| the five sense organs | skin, tongue, nose, eyes, ears |
| skin | body's largest organ |
| two functions [jobs] of the skin | protects the body, provides the sense of touch |
| receptors | they collect information and pass it on to sensory neurons |
| the sense centered in tongue | taste |
| taste buds | these respond to four basic tastes: bitter, sour, sweet, salty |
| smell | sense activated by receptors in the nose |
| vision | sense of sight |
| sight | sense activated by receptors in the eyes |
| parts of the eye | lens, pupil, cornea, iris, retina, optic nerve |
| hearing | sense activated by receptors in the ears |
| sound waves | vibrations that move through the air |
| eardrum | membrane at end of ear canal |
| reflex | automatic reaction to a stimulus |
| brain waves | nerve impulses from the brain |
| drug | a substance that can affect the function of body cells and tissues |
| caffeine | drug found in coffee, some teas, chocolate, some soft drinks |
| alcohol | drug found in beer, wine, and other similar beverages |
| nicotine | drug found in tobacco products such as cigarettes, chewing tobacco, and snuff |
| illegal drugs | drugs whose use is against the law |
| substance abuse | the misuse of any drug |
| smoking | the major cause of lung cancer |
| nicotine | drug found in tobacco |
| addiction | the condition in which a person has extreme difficulty in stopping the use of a drug |
| stimulant | a type of drug that increases activity of the nervous system [ex. - nicotine] |
| depressant | a type of drug that decreases activity of the nervous system [ex. - alcohol] |
| hallucinogen | a type of drug that alters perceptions and awareness [ex. - marijuana] |
| narcotic | a type of drug that depresses the function of the brain and nervous system [ex. - heroin] |
| inhalant | a type of drug that increases activity of the nervous system [ex. - sniffing glue] |
| steroid | a type of drug that increases body mass and strength [ex. - Winstrol-V] |
| alcoholism | a disease that causes a person to be addicted to alcohol |
| BAC | blood alcohol concentration test |
