A&P Test 4 Study Guide (Chandler)

Meninges

three protective membranes that surround the brain and spinal cord

dura mater, arachnoid mater, pia mater

Ventricles of the brain

canals in the brain that contain cerebrospinal fluid

lateral, third, fourth

Cerebral aqueduct

connects the third and fourth ventricles

Choroids plexus

forms cerebrospinal fluid

CSF function

nutritive and protective, helps maintain stable ion concentrations in CNS

Spinal cord divisions

cervical, thoracic, lumbar, sacral, filum terminale

Reflex arcs

automatic, subconscious responses to stimuli within or outside the body

receptor (sensory or afferent neuron) -> central nervous system (motor or efferent neuron) -> effector (muscle or gland)

Frontal lobe function

involved in motor function: problem solving, memory, judgment, impulse control

Parietal lobe function

somatic sensory processing

Temporal lobe function

hearing and smell

Occipital lobe function

visual processing

Insula lobe function

memory, taste, and integration of the activities of the other cerebral lobes

Cerebrum function

higher order functions: thinking, personality, sensations, movements, memory

Sulci

grooves

Gryri

ridges

Longitudinal fissure

separates cerebral hemispheres

Transverse fissure

separates cerebrum from cerebellum

Lateral fissure

separates temporal lobe from frontal and parietal lobes

Cerebral cortex

thin layer of grey matter surrounds outermost portion of the cerebrum

Broca's area

speech production

Wernicke's area

language comprehension

Diencephalon

thalamus and hypothalamus

Thalamus

the brain's sensory control center, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

Hypothalamus

a neural structure lying below the thalamus; directs eating, drinking, body temperature; helps govern the endocrine system via the pituitary gland, and is linked to emotion

Brainstem

responsible for automatic survival functions

Midbrain

A small part of the brain above the pons that integrates sensory information and relays it upward.

Medulla oblongata

the continuation of the spinal cord within the skull, forming the lowest part of the brainstem and containing control centers for the heart and lungs (also coughing, sneezing, swallowing, vomiting)

Pons

A brain structure that relays information from the cerebellum to the rest of the brain; sleep and arousal

Limbic system

neural system located below the cerebral hemispheres; associated with emotions, drives, and memory

Cerebellum

2 hemispheres connected by vermis; cerebellar peduncles (and midbrain); integrates information about position of body parts, coordinates skeletal muscles, maintains posture

Arbor vitae

white matter of the cerebellum

Cranial Nerve I

Olfactory
sensory, smell

Cranial Nerve II

Optic
sensory, vision

Cranial Nerve III

Oculomotor
motor, raise eyelids, move eyes, focus lens, adjust light enetering, proprioceptors

Cranial Nerve IV

Trochlear
primarily motor, proprioceptors, move eyes

Cranial Nerve V

Trigeminal
both, sensation to the face, chewing

Cranial Nerve VI

Abducens
primarily motor, move eyes, proprioceptors

Cranial Nerve VII

Facial
both, taste receptors, facial expressions, tear glands, salivary glands

Cranial Nerve VIII

Vestibulocochlear
sensory, equilibrium receptors, hearing receptors

Cranial Nerve IX

Glossopharyngeal
both, pharynx, tonsils, tongue, carotid arteries, salivary glands, larynx, esophagus

Cranial Nerve X

Vagus
both, speech, swallowing, viscera of thorax and abdomen, pharynx, larynx, esophagus

Cranial Nerve XI

Accessory
primarily motor, muscles of soft palate, pharynx, larynx, spinal branch to neck and back muscles

Cranial Nerve XII

Hypoglossal
primarily motor, muscles of tongue, some proprioceptors

C1-C8

cervical nerves

T1-T12

thoracic nerves

L1-L5

lumbar nerves

S1-S5

sacral nerves

Dorsal root

sensory (afferent)
come in through dorsal nerves

Dorsal root ganglion

cell bodies of sensory neurons

Ventral root

motor (efferent), go out through ventral

Spinal nerve

union of ventral and dorsal roots

Dermatome

the region of a spinal nerve innervates

Plexuses

network formed by anterior/ventral branches of spinal nerves

C1-C4 cervical
C5-T1 brachial
Intercostal nerves

Somatic nerve fibers

convey information that controls the body's voluntary muscular movements (motor/efferent)

Visceral nerve fibers

innervate blood vessels, glands, and viscera (sensory/afferent)

autonomic nervous system (ANS)

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart).

sympathetic nervous system

prepares for fight-or-flight (increases rate of respiration, heart rate, adrenaline, vessels in muscles dilate, blood vessels in skin constrict, pupils dilate)

parasympathetic nervous system

prepares for rest-and-digest (slows heart rate, become tired, slower respirations)

Preganglionic fibers

nerve fibers of the autonomic nervous system that connect the CNS to the ganglia

Postganglionic fibers

nerve fibers that present in the autonomic nervous system which connects the ganglion to the effector organ

Cholinergic

parasympathetic
rest-and-digest

Adrenergic

sympathetic
fight-or-flight
(Acetylcholine)

Concussion

Brain is jarred against cranium. Typically characterized by a loss of consciousness, loss of memory, mental cloudiness, or headache

CVA

cerebrovascular accident (stroke)
sudden interruption in blood flow to brain (blockage or rupture)

TIA

transient ischemic attack (mini stroke)
narrowing of blood vessels in the brain, causing a decrease in blood flow and oxygen supply

General senses

receptors are widely distributed: skin, various organs, joints

Special senses

specialized receptors confined to structures: vision, hearing, taste, smell

Chemoreceptors

smell and taste

Nociceptors

pain receptors

Thermoreceptors

respond to changes in temperature

Mechanoceptors

sensitive to pressure, touch, vibration, and bending of skin

Photoreceptors

respond to light

Proprioceptors

sense tension (such as in muscles)

Baroreceptors

sense to pressure (such as blood pressure)

Sensory adaptation

a decrease in sensitivity to a constant level of stimulation

Such as not noticing the noise of traffic while in class

Meissner's corpuscles

sensitive touch receptors in the dermis

abundant in hairless portions of skin, lips; fine touch

Pacinian corpuscles

Common in deeper subcutaneous tissues, tendons and ligaments

Detect heavy pressure and vibrations

Free nerve endings

common in epithelial tissues, simplest receptor

respond to pain and temperature, sense itching

Referred pain

pain that is felt in a location other than where the pain originates

caused by nerve crossings; visceral pain

Acute pain

myelinated, sharp pain, well localized

Chronic pain

unmyelinated, dull throbbing, hard to pinpoint

Role of thalamus in pain

allows person to be aware of pain

Role of cerebral cortex in pain

judges intensity, source; emotional and motor responses

Basic ear anatomy

auditory canal, eardrum, ossicles, cochlea, nerves, brain

Pathway of hearing

When sound enters the ear, it is funneled into the external acoustic meatus by the outer structure called the auricle. This sound vibrates the tympanic membrane which vibrates the auditory ossicles (malleus, incus, stapes). The last of these moves back and forth in the oval window, and this motion causes a signal to be formed and taken to the brain by the acoustic/cochlear nerve.

Static equilibrium

the perception of the orientation of the head when the body is stationary

Dynamic equilibrium

semicircular canals, sense rotation and movement of head and body. OToliths move and stimulate hair cells (crystal like stones on top of hair cells)

Role of semicircular canals in equilibrium

needed for dynamic equilibrium

Role of macula in equilibrium

needed for static equilibrium

Eyelid function

Moisten, cover, brush debris from eye

Conjunctiva function

Secretes mucus to lubricate the eye (forms seal between the surface of the eye and the eyelid to prevent particles from getting trapped behind the eye)

Lacrimal apparatus function

produces, distributes, and removes tears

accomodation of lens

thickening of the lens to see close objects

Path of light through the eye

The path of light from outside your eye to your retina starts with light going through your cornea, passing through the aqueous humor; through the pupil, who's size is controlled by the iris. The light then passes through the lens and through the vitreous humor, finally hitting the retina, which contains rods and cones which sense light. The first of these light-sensitive structures have a long and thin shape, and are sensitive to low light and black & white images. The second has a short and blunt shape, and is sensitive to color images.

Myopia

nearsightedness; problems with the shape of the cornea or lens

Hyperopia

farsightedness; problems with the shape of the cornea or lens

Presbyopia

loss of elasticity of the lens of the eyes