| A | B |
|---|
| Stimuli | changes in the environment causing a response |
| neurons | nerve cells |
| cell body | largest part of the neuron, contains the nucleus |
| dendrites | tiny branching parts of neurons, carry messages to cell body |
| axon | long tail of neuron, carries messages away from body cell |
| receptors | cells that receive information from surroundings |
| sensory neurons | carry messages from receptors to spinal cord |
| inter neurons | connect to motor neurons and process information |
| motor neurons | send messages to muscle cell or body gland |
| nerves | carry messages from brain to spinal cord to body and back |
| brain | sorts information and decides how body should respond |
| brain stem | controls involuntary actions, like heart beat, breathing |
| cerebellum | coordinates movement of muscles, makes actions smooth and balanced |
| cerebrum | largest part of brain, controls intelligence, personality, five senses |
| central nervous system (cns) | brain and spinal cord |
| pheripheral nervous system (pns) | network of nerves that branch out from cns to all body parts |
| vision | eyes focus light rays to produce images |
| sclera | outer protective layer of eye, white of eye |
| cornea | clear area of eye that light enters |
| iris | colored part of eye |
| pupil | opening in middle of eye, regulates amount of light entering eye |
| lens | focuses light rays |
| retina | screen that light rays get focused on |
| rods | see black and white |
| cones | see color |
| eardrum | tightly stretched membrane that separates ear canal from middle ear, vibrates to produce sound |
| middle ear | contains hammer, anvil, stirrup, which vibrate when sound waves hit eardrum |
| inner ear | fluid portion of ear containing cochlea |
| cochlea | contains nerves for volume |
| semicircular canals | fluid filled tubes, responsible for balance |
| sweet, sour, salt, bitter | 4 basic tastes |
| skin | largest sense organ |
| hormones | chemicals that regulate body activity |
| endocrine system | made of glands that produce chemical messengers called hormones |
| hypothalamus | regulates activity of all other endocrine glands, at base of brain |
| pituitary | stimulates growth, at base of brain |
| thyroid | increases rate of metabolism, levels of calcium and phosphorous, at base of neck |
| adrenal | increases heart rate, blood pressure, blood sugar, breathing rate, is above kidneys |
| pancreas | helps liver store sugar, regulates sugar levels, is near stomach |
| testes | produces male sex characteristics, in scrotum |
| ovaries | produces female sex characteristics, is in pelvic area |
| nervous system | body's communication network |
