PHYL 141L Unit 3 Exam

spinal cord

pathway connecting the brain and the peripheral nervous system

autonomic nervous system

automatically regulates glands, internal organs, and blood vessels, pupil dilation, digestion, and blood pressure

somatic nervous system

carries sensory information and controls movement of the skeletal muscles

parasympathetic division

maintains body functions under ordinary conditions; saves energy

sympathetic division

prepares the body to react and expand energy in times of stress

sensory system (afferent)

carries messages from senses to CNS

motor system (efferent)

carries messages from CNS to muscles and glands

rostral

anterior side of the neural tube

caudal

posterior side of the neural tube

mesencephalon

midbrain

rhombencephalon

hindbrain

telencephalon

part of the prosencephalon (forebrain)

diencephalon

part of the prosencephalon (forebrain)

mesencephalon (secondary brain vesicle)

midbrain

metencephalon

part of the rhombencephalon

myelencephalon

part of the rhombencephalon

cerebrum

adult brain structure the telencephalon turns to

diencephalon, retina

adult brain structure the diencephalon turns to

brain stem: midbrain (midbrain)

adult brain structure the mesencephalon turns to

brain stem: pons (pons)

adult brain structure the metencephalon turns to

cerebellum

adult brain structure the metencephalon turns to (not pons)

brain stem: medulla oblongata (medulla oblongata)

adult brain structure the myelencephalon turns to

central canal

contains the spinal cord

corpus callosum

what connects the left and right cerebral hemispheres

left hemisphere

side of the brain linked to logic and analytic thinking

right hemisphere

Side of the brain that is linked with creativity and emotional processing

frontal

Personality, decision making, movement, speech product

parietal

Special awareness/relationships, somatosensory

temporal

Speech understanding, sense of smell, hearing

occipital

Vision

Insula

gustatory and sensorimotor processing, risk-reward behavior, autonomics, pain pathways, and auditory and vestibular functioning

Broca’s area

located in the left frontal lobe, this area controls speech production and articulation. It activates the muscle used to speak words

Wernicke’s area

located in the left temporal lobe, this area controls the ability to understand and select words to use when speaking. It processes the understanding of words and sends signals to Broca’s area.

diencephalon

acts as a primary relay and processing center for sensory information and autonomic control

thalamus

is considered to be a relay station that relays information between different subcortical areas and the cerebral cortex

hypothalamus

acts as the body’s control center and helps manage your body temperature, hunger and thirst, mood, sex drive, blood pressure and sleep

pineal gland

is part of the endocrine system and secretes the hormone melatonin. Its main job is to help control the circadian cycle of sleep and wakefulness

pituitary gland

(located at base blow the hypothalamus, sits in own little chamber under your brain known as the sella turcica) releases several important hormones and controls the functions of many other endocrine system glands

midbrain

the top part of the brainstem. Involved in motor control, particularly eye movements and processing of vision and hearing

pons

the middle portion of the brainstem that coordinates face and eye movements, facial sensations, hearing and balance

medulla oblongata

the bottom part of the brainstem that regulates breathing, heartbeat, blood pressure and swallowing

cerebellum

processes input from other areas of the brain, spinal cord, and sensory receptors to coordinate smooth movements of the skeletal muscular system, controls balance and other complex motor functions

gyri

ridges

sulci

Shallow grooves

fissures

Deep grooves

white matter

myelinated and unmyelinated axons, serves to transmit signals to other regions of the brain, spinal cord, and body

gray matter

short, unmyelinated neurons and cell bodies, receive information and regulate outgoing information, the most outer layer of the brain

ventricles

Fluid-filled chambers that are continuous to one another and to central canal of spinal cord

choroid plexus (composed of ependymal cells)

what membrane lines the ventricles

arachnoid mater

the middle meninx, weblike shape. Underlies the dura mater and is partially separated from the from it by the subdural space

pia mater

innermost meninx, highly vascular and clings tenaciously to the surface of the brain, following its gyri

olfactory (I)

carries afferent impulses for sense of smell (nose)

optic (II)

carries afferent impulses associated with vision (eye)

oculomotor (III)

somatic motor fibers to inferior oblique and superior, inferior, and medial rectus muscles, which direct eyeball, and to levator palpebrae muscles of the superior eyelid; parasympathetic fibers to smooth muscle controlling lens shape and pupil size (all eye muscles except those supplied by IV and VI)

trochlear (IV)

provides somatic motor fibers to superior oblique muscle that moves the eyeball (superior oblique muscle)

trigeminal (V)

major sensory nerve of face, conducts sensory impulses from skin of face and anterior scalp, from mucosae of mouth and nose, and from surface of eyes; mandibular division also contains motor fibers that innervate muscles of mastication and muscles of floor of mouth (face, sinuses, teeth, etc.)

abducens (VI)

carries somatic motor fibers to lateral rectus muscle that abducts the eyeball (external rectus muscle)

facial (VII)

supplies somatic motor fibers to muscles of facial expression and the posterior belly of the digastric muscle; parasympathetic motor fibers to lacrimal and salivary glands; carries sensory fibers from taste receptors to anterior tongue (muscles of the face)

vestibulocochlear (VIII)

vestibular branch transmits impulses associated with sense of equilibrium from vestibular apparatus and semicircular canals; cochlear branch transmits impulses associated with hearing from cochlea. Small motor component adjusts the sensitivity of the sensory receptors (inner ear)

glossopharyngeal (IX)

somatic motor fibers serve pharyngeal muscles, and parasympathetic motor fibers serve salivary glands; sensory fibers carry impulses from pharynx tonsils, posterior tongue (taste buds), and from chemoreceptors and pressure receptors of carotid artery (pharyngeal musculature)

vagus (X)

fibers carry somatic motor impulses to pharynx and larynx and sensory fibers from same structures; very large portion is composed of parasympathetic motor fibers, which supply heart and smooth muscles of abdominal visceral organs; transmit sensory impulses from viscera (heart, lungs, bronchi, gastrointestinal tract)

accessory (XI)

provides somatic motor fibers to sternocleidomastoid and trapezius muscles (sternocleidomastoid and trapezius muscles)

hypoglossal (XII)

carries somatic motor fibers to muscles of tongue (muscles of the tongue)

sensory neuron

carries the impulse from the receptor to the spinal cord

integration center

processes the information and directs the response to the motor neuron

Motor neuron

conducts the impulse from the spinal cord to an effector

Inborn (intrinsic) reflex

rapid, involuntary, predictable motor response to stimulus (maintain posture, control visceral activities, can be modified by learning and conscious effort)

Learned (acquired) reflexes

result from practice or repetition (e.g., driving skills)

somatic reflexes

activate skeletal muscle

Autonomic (visceral) reflexes

activate visceral effectors (smooth or cardiac muscle or glands)

stretch reflex

a feedback mechanism that controls muscle length by causing muscles to contract when stretched, muscle spindles detect the stretch and send the information to the central nervous system. Prevents muscles from being overstretched and injured

tendon reflex

a negative feedback mechanism that controls muscle tension. Tendon organs detect changes in muscle tension caused by contraction, not passive stretching. The tendon reflex is less sensitive than the stretch reflex, but it can override the stretch reflex when tension is high

sensory receptors

Specialized to respond to changes in the environment (stimuli)

Mechanoreceptors

respond to touch, pressure, vibration, and stretch

Thermoreceptors

sensitive to changes in temperature

photoreceptors

respond to light energy (e.g., retina)

chemoreceptors

respond to chemicals (e.g., smell, taste, changes in blood chemistry)

nociceptors

sensitive to pain-causing stimuli (e.g., extreme heat or cold, excessive pressure inflammatory chemicals)

exteroceptors

respond to stimuli arising outside the body, receptors in skin for touch, pressure, pain, and temperature, most special sense organs

interoceptors (visceroceptors)

respond to stimuli arising in internal viscera and blood vessels, sensitive to chemical changes, tissue stretch and temperature changes, sometimes cause discomfort but usually person is unaware of their workings

Proprioceptors

respond to stretch in skeletal muscles, tendons, joints, ligaments and connective tissue coverings of bones and muscles, inform brain of one’s movements

general senses

include tactile sensations (touch, pressure, stretch, vibration) temperature, pain, and muscle sense

special senses

Vision, hearing, equilibrium, smell, and taste

All are housed in complex sense organs

rods

• Dim light, peripheral vision receptors

• More numerous and more sensitive to light than cones

• No color vision or sharp images

cones

• Vision receptors for bright light

• High-resolution for color vision

lateral rectus (VI)

moves eye laterally

medial rectus (III)

moves eye medially

superior rectus (III)

elevates eye and turns it medially

inferior rectus (III)

depresses eye and moves it medially

inferior oblique (III)

elevates eye and moves it laterally

superior oblique (IV)

depresses eye and moves it laterally

facial, glossopharyngeal, vagus

cranial nerves that carry taste sensation

gustatory receptors

used for sense of taste

semicircular canals and vestibule

structures involved with equilibrium (balance)

cochlea

structure involved with hearing