M3L1

taste absolute threshold

1 teaspoon of sugar in 2 gallons of water

smell threshold

1 drop of perfume in 6 room apt

ganglion

A cluster of nerve cell bodies, often of similar function, located in the PNS.

hammer

A tiny bone that passes vibrations from the eardrum to the anvil

anvil

A tiny bone that passes vibrations from the hammer to the stirrup

lens

Focuses light onto retina

Aplitude

The distance above or below the center line of a waveform. volume

electromagnetic energy

The energy of light and other forms of radiation.

difference threshold

The minimum amount of difference that can be detected between two stimuli

cochlea

a coiled, bony, fluid-filled tube in the inner ear; sound waves traveling through the cochlear fluid trigger nerve impulses

Iris

a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening

vitreous gel

a soft, clear, jelly-like mass that contains millions of fine fibers

eardrum

a thin membrane that marks the beginning of the middle ear; sound waves cause it to vibrate

soundwaves

a wave of compression and rarefaction, by which sound is propagated in an elastic medium such as air.

vision absolute threshold

candle flame 30 miles away

optic nerve

carries neural impulses from the eye to the brain

What color has the longest wavelength?

red

stirrup

device for securing a horseman's feet, enabling him to wield weapons more effectively. First evidence of the use of stirrups was among the Kushan people of northern Afghanistan in approximately the first century C.E.

bipolar cells

eye neurons that receive information from the retinal cells and distribute information to the ganglion cells

greater frequency

higher pitch

rods and cones

in the retina, receives images that have passed through the lens of the eye

greater amplitude

louder sound

floaters

one or more spots that appear to drift or float across the visual field

eye

organ that detects environmental stimuli and converts it to neural signals

visable light

portion of the electromagnetic spectrum that is visible to the human eye.

Cones

retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations.

Rods

retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond

macula

round darker area of the ocular fundus that mediates vision only from the central visual field

achromatopsia

severe congenital deficiency in color perception; also called complete color blindness

pupil

the adjustable opening in the center of the eye through which light enters

middle ear

the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea's oval window

Retina

the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information

absolute threshold

the minimum stimulation needed to detect a particular stimulus 50 percent of the time

Frequency

the number of complete wavelengths that pass a point in a given time pitch

outer ear

the outermost part of the ear, consisting of the pinna and the external auditory canal

Sensation

the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment

electromagnetic spectrum

the range of wavelengths or frequencies over which electromagnetic radiation extends.

vestibular sense

the sense of body movement and position, including the sense of balance

Cornea

the transparent layer forming the front of the eye.

semicircular canals

three canals within the inner ear that contain specialized receptor cells that generate nerve impulses with body movement

pinna

visible part of the ear that protrudes from the head funnels sound waves to auditory canal

hearing absolute threshold

watch ticking at 20 feet in a quiet room

touch absolute threshold

wing of fly on cheek dropped from 1 cm