Exam 4 short answer Flashcards
Function of the dorsal root
transmits sensory information
Function of dorsal root ganglia
relay the sensory nerve impulses from the periphery to the peripheral nervous system
Functions of ventral root
allow motor neurons to exit the spinal cord.
Describe the 3 layers of meninges
Dura mater: Superficial meninx, composed of dense, irregular connective tissue
Arachnoid mater: Middle meninx; Composed of epithelium and a delicate network of collagen and elastic fibers ( resembles spider web)
Pia mater: Innermost meninx ; Adheres to the surface of the spinal cord and the brain; Composed of collagen and elastic fibers
What are the functions of cerebrospinal fluid?
Serves as a shock absorber
– Carries nutrients, wastes, and dissolved gases
Functions of posterior horn
sensory processing
Functions of lateral horn
»Contraction of cardiac and smooth muscle tissue
»Glandular secretion
Functions of anterior horn
Skeletal muscle contraction
List the 4 major plexuses
cervical, brachial, lumbar, sacral
What are the functions of the plexuses: cervical, brachial, lumbar, and sacral ( Name at least one major nerve for each plexus)
overall function: communicate information to your brain about pain, temperature, and pressure.
cervical: Supplies the skin and muscles of the head,
neck, thoracic cavity, and diaphragm. MN: Phrenic nerve
Brachial: Supplies the shoulders and upper limbs. MN: subscapular nerve
Lumbar: Supplies the abdominal wall, external genitals, and part of the lower limbs. MN: femoral nerve
Sacral: Supplies the buttocks, perineum, and parts of the lower limbs MN: sciatic nerve.
What is a stretch reflex? Provide an example. Describe the withdrawal reflex and the crossed
extensor reflex.
stretch reflex: the contraction of a muscle in response to its passive stretching
Ex: striking the patellar tendon with a reflex hammer
Withdrawl reflex: the automatic withdrawal of a limb from a painful stimulus
Crossed extensor refelx: Crossing of sensory impulses within the reflex center to
produce an opposite effect
Identify the 4 parts of the brain along with major functions.
Frontal: reasoning, planning, parts of speech, movement, emotions, and problem solving
temporal: perception, auditory stimuli, memory, and speech
parietal: movement, orientation, recognition, perception of stimuli
occipital: visual processing
What fills the ventricles?
cerebrospinal fluid
Define the blood-brain barrier.
The separation of the circulating blood and the brain extracellular fluid (CSF) in the CNS
Know the functions of the brain stem (midbrain, pons, medulla) and the cerebellum.
Midbrain: movement of body and head
Pons: motor control, sensory analysis
Medulla: vital body functions (breathing, heart rate)
cerebellum: “little brain” , movement, posture, balance
hypothalamus Functions
Regulates body temperature –sweating/shivering
- Regulates hunger and satiety in response to nutrient blood levels or hormones
- Regulates water balance and thirst
- Regulates sleep-wake cycles
- Controls endocrine system
Understand these structures of the diencephalon: thalamus, hypothalamus, limbic system, pineal
gland. What are their functions?
thalamus: Sorts, edits, and relays ascending input
hypothalamus: Controls autonomic nervous system
limbic system: behavioural and emotional responses
pineal gland: to receive information about the state of the light-dark cycle and secretre melatonin
Know the functions of the lobes of the brain. (frontal, parietal, temporal, occipital, insula)
Frontal: Emotions, judgement, understanding, personality self awareness
parietal: Touch, pain & temp sensations from the opposite side of the body
Temporal: Auditory perception, memory.
Occipital: Visual perception, color recognition
Insula: controls autonomic functions
sympathetic NS vs parasympathetic NS
- Sympathetic: fight or flight; speeds body functions up (heart rate, respiratory rate, dilate
pupils, increase glucose) - Parasympathetic: rest and digest; slows things down (decreases HR, RR, increases digestion
and elimination)
know the functions of Medulla, Hypothalamus, Limbic system
**Understand the important role of the hypothalamus
Medulla: vital center: regulates cardiac, vasomotor, respiratory system.
Hypothalamus: regulates visceral functions, temperature, hunger, thirst, water,
electrolyte balance
Limbic: controls emotional responses and feelings
**Important function: center of ANS activity
Why is perception of pain important? What is referred pain? Provide several examples.
refered pain: ccur due to sensory impulses from two regions following a common nerve pathway to brain
ex: The pain of a heart attack is frequently
felt in the left arm
perception of pain is important to let the body know that there is something wrong so it can correct it.
Describe the olfactory nerve pathway.
Olfactory nerves > olfactory bulbs >
olfactory tracts > limbic system (for
emotions) and olfactory cortex (for
interpretation)
Describe the visual pathway. Include the basic eye and nervous structures: the eye: cornea, iris,
pupil, retina, lens, anterior cavity, aqueous humor, posterior cavity, vitreous body; optic nerve,
optic chiasm, optic radiations, thalamus, occipital cortex.
light enters the eye, sending signals to the retina. It is continuous with the optic nerve and receives images of external objects and transmits visual impulses to the brain.
Describe the hearing pathway: include structures of the ear and nervous system: auricle, external
acoustic meatus, tympanic membrane, auditory ossicles (malleus, incus, stapes), auditory tube,
bony labyrinth (vestibule, semicircular canals, cochlea, perilymph), membranous labyrinth
(endolymph), hair cells, otoliths, vestibulocochlear nerve, thalamus, temporal lobe.
- The auricle collects sound waves and directs them into the external acoustic meatus
- Vibrations are transmitted to the auditory ossicles
- fluid pressure waves are created
- Vibrations are passed to the basilar membrane
- cells depolarize and nerve impulses are generated
- Nerve impulses travel to the auditory cortex
