PSU Bio 161 Test 3

ganglion

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

tectorial membrane

A membrane located above the basilar membrane; serves as a shelf against which the cilia of the auditory hair cells move

voltage-gated calcium channels

A membrane protein forming a pore that is permeable to Ca2+ ions and gated by depolarization of the membrane.

cerebral spinal fluid

A solution that fills the hollow cavities of the brain and circulates around the brain and spinal cord. Provides nourishment, cushions, and removes wastes.

organ of corti

Center part of the cochlea, containing hair cells, canals, and membranes

cranial nerve VII

Facial - controls most facial expressions & secretion of tears & saliva & taste; located in internal auditory meatus

cerebrum

Largest part of the brain; responsible for voluntary muscular activity, vision, speech, taste, hearing, thought, and memory.

Retina

Light sensitive layer of the eye; contains rods and cones

dialator

Opens, enlarges or expands

proprioceptors

Sensory receptors, located in the muscles and joints, that provide information about body position and movement.

ciliary body

Structure surrounding the lens that connects the choroid and iris. It contains ciliary muscles, which control the shape of the lens, and it secretes aqueous humor.

tympanic membrane

The eardrum. A structure that separates the outer ear from the middle ear and vibrates in response to sound waves.

hair cells

The hairlike sensory receptors for sound, which are embedded in the basilar membrane of the cochlea.

semi-circular canals

The part of the ear that controls the vestibular sense.

cochlea

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

cochlear duct

a fluid filled cavity within the cochlea that vibrates when sound waves strike it

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

basilar membrane

a structure in the inner ear that undulates when vibrations from the ossicles reach the cochlear fluid

EPSP

a.k.a excitatory postsynaptic potential, causes depolarization of postsynaptic neuron

IPSP

a.k.a. inhibitory postsynaptic potential, causes hyperpolarization of postsynaptic neuron

nerve

bundle of axons in PNS

ventricles

canals in the brain that contain cerebrospinal fluid

efferent division

carries motor commands from CNS to PNS muscles and glands

afferent division

carries sensory information from PNS sensory receptors to CNS

Melanocytes

cells that produce melanin

neruotransmitter

chemical messenger released at the end of a nerve cell

sphincter

circular ring of muscle that constricts a passage or closes a natural opening

bipolar neuronal layer

communicate info from rods and cones to ganglionic cells

hindbrain

contains cerebellum, pons, and medulla; primitive responses (heart rate, breath rate)

brainstem

contains midbrain, pons, and medulla oblongata

Meninges of the brain

dura mater, arachnoid mater, pia mater

lacrimal gland

gland located in the upper outer region above the eyeball that secretes tears

visceral sensory receptors

input from internal organs, chemoreceptors

midbrain

integrates info from special senses and movement

frequency of action potentials

interpreted in the brain as the strength of the stimulus (stronger stimulus=more action potentials)

external ear (auditory canal)

is lined with skin, hairs, sebaceous glands, and ceruminous glands and runs through external acoustic meatus in the temporal bone

scala vestibuli

leads from oval window to apex of cochlea; transmits vibrations

cerebellum

located at the rear of the brainstem, a large structure of the hindbrain that controls fine motor skills.

Forebrain

made up of the cerebrum and diencephalon, integrates info to help regulate complex organ systems, integrates conscious thought

oval window

membrane at the entrance to the cochlea through which the ossicles transmit vibrations

choroid

middle, vascular layer of the eye, between the retina and the sclera

postsynaptic cell

neuron that receives message

presynaptic cell

neuron that sends message, gives off the electrical signal

postganglionic neuron

neurons of the autonomic nervous system that form synapses directly with their target organ

cholinergic neurons

neurons that release acetylcholine

adrenergic neurons

neurons that release norepinephrine

tunica fibrosa

outer fibrous layer sclera and cornea

pons

part of the brainstem, a brain structure that relays information from the cerebellum to the rest of the brain

nasolacrimal duct

passageway for tears from the lacrimal sac into the nose

somatic sensory

receives sensory info signals from receptors in the skin, muscles, bones, and joints

scala tymapni

recieves vibrations from scala vestibuli

tunica nervosa

retina

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

gyri

ridges of the brain

synapse

space between neurons, where the conversion from an electrical signal to a chemical signal occurs

summation

sum of all local potential chances at the synapses of a postsynaptic cell

diencephalon

thalamus, hypothalamus, epithalamus

sight

the ability to see

auditory canal

the area that sound waves pass through to reach the eardrum

medulla

the base of the brainstem; controls heartbeat and breathing

middle ear

the chamber between the eardrum and cochlea containing three tiny bones that concentrate the vibrations of the eardrum on the cochlea's oval window

aqueous humor

the clear fluid filling the space in the front of the eyeball between the lens and the cornea.

sympathetic nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations, fight or flight

parasympathetic nervous system

the division of the autonomic nervous system that calms the body, conserving its energy, rest and digest

preganglionic neuron

the first neuron in a series that transmits impulses from the CNS

inner ear

the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs

ganglion cells

the specialized cells which lie behind the bipolar cells whose axons form the optic nerve which takes the information to the brain

Cornea

the transparent layer forming the front of the eye.

dura mater

thick outermost layer of the meninges

pia mater

thin, delicate, innermost membrane of the meninges.

ossicles

three tiny bones in middle ear; malleus, incus, stapes

sulci

valleys of the brain

tunica vasculosa

vascular layer; choroid, ciliary body & iris; provides nourishment

arachnoid mater

weblike middle layer of the three meninges

Sclera

white of the eye