sends impulses to cerebrum
retina attaches to nerve, no vision
layer of receptor cells (rods and cones) that line back of the eye; changes light to impulses
What are rods and cones?
receptor cells in the retina that send impulses to cerebrum which turns image right-side up.
Which receptor cells work best in dim light?
Rod cells - they enable you to see black, white, and shades of gray.
allows light to enter; size of pupil adjusted by muscles in the iris.
clear tissue that covers the front of the eye and bends light into pupil
flexible structure that focuses light onto retina
controls amount of light entering into the eye - is as individual as a finger print and even more detailed.
pull lens for focusing
shapes eyeball; holds retina
trouble seeing objects far away; concave lens for correction
trouble seeing objects close up; convex lens for correction
What is the function of ears
sense organs that respond to stimulus of sound; ears convert sound to nerve impulses that your brain interprets
What are the three regions of the ear
outer ear, middle ear, inner ear
describe the outer ear
funnel-shaped to collect sound
describe the middle ear
consists of the eardrum, hammer, anvil and stirrup
What is the function of the eardrum
separates the outer ear from the middle ear; it's a membrane that vibrates when sound strikes it
What is the function of the hammer, anvil and stirrup
smallest bones in the body that occur in the middle ear; vibration passes from the hammer to the anvil to the strirrup.
What is the function of the cochlea
Occurs in the inner ear; tranfers impulses to the brain through the auditory nerve
What are the semicircular canals?
structures in the inner ear that controls balance
How are the senses of smell and taste similar?
Work closely together; both depend upon chemicals in the air and in food. The chemicals trigger responses in receptors in the nose and mouth.
How is information about smell sent to the brain?
THrough the olfactory nerve
What basic tastes can the tongue distinguish
sweet, salty, sour, bitter, and umami (brothy and meaty flavors)
WHat is the largest sense organ
WHat kind of receptors does the skin have?
different kinds that respond to a number of stimuli.
Where are receptors that respond to light touch and texture located?
upper part of the dermis
Where are receptors located that repond to pressure
Deeper in the dermis
What other receptors are located in the dermis
heat, pain and cold
What is concidered to be a drug?
anything other than food that affects the body, primarily the nervous system.
What is considered to be a medicine?
drugs that treat medical problems
What are the two classes of medicine?
prescription and OTC
What do stimulants do to your body and give examples?
speed up CNS. Cocaine, nicotine, caffine
What do depressants do to your body and give examples?
slow down CNS. Alcohol, heroin
What do inhalents and hallucinogens do to your body and give examples?
altre perception. LSD, paint thinner
What do anabolic steroids do to your body and give examples?
increase muscle and strength. Heart and liver damage