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24-25 HUMAN ANATOMY > The Nervous System > Flashcards

The Nervous System Flashcards

1
Q

Describe the main features of the nervous system

A
  • Maintains internal coordination with electrical/chemical signals
  • Contains CNS (brain+spinal cord) and PNS (sensory and motor divisions)
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2
Q

Describe the CNS

A
  • Central nervous system
  • Brain and spinal cord
  • Process, store and retrieve information
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3
Q

Describe the PNS

A
  • Peripheral nervous system
  • Delivers signals to/out of CNS
  • Sensory
    • Sends signals to CNS
    • Brings sensation
  • Motor
    • Sends signals from CNS to glands/muscles
    • Brings response
  • Somatic
    • Connect to skin, muscle, or bone joint
    • Voluntary muscles
  • Visceral
    • Connect to internal organs
    • Involuntary muscles
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4
Q

Describe neurons and its properties

A
  • Functional unit of the nervous system
  • Excitability: Responsive to stimuli
  • Conductivity: Transduce signals
  • Secretion: Secrete neurotransmitter to stimulate another neuron
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5
Q

What are the functional classes of neurons, based on function?

A
  • Sensory (afferent)
    • Transduce signals from receptors to CNS
  • Interneurons
    • Integrative function
    • 90% of neurons in human body
  • Motor (efferent)
    • Send signals to muscles/glands
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6
Q

Describe the structure of a neuron

A
  • Cell body
    • Soma
    • Organelles e.g. nucleus, mitochondria
    • Neurofibrils: network to maintain shape
  • Dendrites
    • Receive signals from other cells
  • Axons
    • Conduction of signals to other cells
    • Myelin sheath
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7
Q

What are the functional classes of neurons, based on the appearance?

A
  • Multipolar
    • One axon + 2> dendrites
  • Bipolar
    • Two neurites (dendrite or axon) from soma
    • One axon + One dendrite
  • Unipolar
    • One neurite from soma
  • Psuedounipolar
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8
Q

What are the types and functions of neuroglia?

A
  • Protects neurons, aids their function
  • “Stick” neurons together via a framework
  • CNS
    • Oligodendrocyte: Wrap axons to form myelin sheath
    • Ependymal cells: Lines the central cavity, produces cerebral spinal fluid
    • Microglia: Immune cells
    • Astrocytes: Forms supportive framework and blood-brain barrier
  • PNS
    • Schwaan cells: Wraps to ONE myelin sheath, nerve regeneration
    • Satellite cells: Surrounds neurons at ganglion (soma)
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9
Q

What is the myelin sheath?

A
  • Insulating layer around nerve fibre
  • Speed up nerve signal transduction
  • Formed by oligodendrocyte (CNS) and Schwaan cells (PNS)
  • Composed of protein and lipids
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10
Q

What are the functions and forms of synapses?

A
  • Meeting point between neuron and other cells
  • Decision-making device
  • Forms
    • Axodendritic: between axon and dendrite
    • Axosomatic: between axon and soma
    • Axoaxonic: between axon and axon
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11
Q

What are the types of synapses?

A
  • Chemical
    • Separated by synaptic cleft
    • Cell adhesion molecules (CAM) connect pre and post-synaptic neurons
    • Release neurotransmitters
  • Electrical
    • Gap junctions
    • Allows ions to diffuse

Acetylcholine: stimulates muscles
Norepinephrine: stimulates organs

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12
Q

Describe the functions of the spinal cord

A
  • “Information highway” that connects brain with lower body
  • Conduction
  • Neural integration
  • Locomotion: controls repetitive muscle contractions
  • Reflexes: involuntary responses
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13
Q

Describe the surface anatomy of the spinal cord

A
  • Cervical, thoracic, lumbar, sacral regions
  • Enlargement areas
    • Nerve tissues to innervate limbs
    • Cervical: nerves for upper limbs
    • Lumbosacral: nerves to pelvic and lower limbs
  • Cauda equina
    • Innervates pelvic and lower limbs
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14
Q

What are the meninges in the spinal cord?

A
  • Protective membranes
  • Dura mater
    • Outer layer
    • Tough collagenous
  • Arachnoid mater
    • Looser
    • Space filled by CSF (shock absorbance)
  • Pia mater
    • Inner layer
    • Delicate, transparent
    • Anchoring
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15
Q

Describe the cross-sectional anatomy of the spinal cord

Gray and white matter

A
  • Gray matter
    • Contains posterior and anterior horns
    • Lateral horns at thoracic and lumbar regions
    • Gray commissure joins right and left sides
    • Central canal in middle
  • White matter
    • Surrounds gray matter
    • Consists of bundles of axons
    • Posterior, lateral, and anterior columns
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16
Q

What are the spinal tracts?

A
  • White matters in spinal cord
  • Ascending
    • Carry sensory info up the cord to the brain
    • First-order neuron: detects stimulus
    • Second-order neuron: to thalamus
    • Third-order neuron: to sensory cortex
    • Spinothalamic: signals for pain, temp, pressure
  • Descending
    • Carry motor impulses down to muscles
    • Upper motor neuron: from cortex down spinal cord
    • Lower motor neuron: to muscles/organs
  • Decussation (cross-over) may be found
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17
Q

What is a nerve?

A
  • Collection of numerous nerve fibres (axon) bound together
  • Fascicle: collection of axons
  • Nerve: collection of fascicles
  • Mixed nerve: sensory and motor neurons
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18
Q

Name the branches of spinal nerves

A
  • Anterior Ramus
    • Innervate skin and muscles on anterior/lateral side
  • Posterior Root
    • Innervate skin and muscles on back of body
  • Meningeal Branch
    • Innervates meninges, vertebrae, spinal ligaments
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19
Q

What are the nerve plexuses?

A
  • Cervical: C1 to C5, innervate diaphragm, neck, and back muscles
  • Brachial: C5 to T1, innervate upper limb, neck, and shoulder muscles
  • Lumbar: L1 to L4, innervate hip, thigh, scrotum
  • Sacral and Coccygeal: L4 to S4
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20
Q

Clinical application

A
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21
Q

What are the three major parts of the brain?

A
  • Cerebrum
    • Left and right hemispheres
    • Separated by longitudinal fissure
    • Connected by Corpus callosum
    • Gyrus: thick folds
    • Sulcus: deep grooves
  • Cerebellum
    • Separated by cerebrum by transverse cerebral tissue
  • Brainstem
    • Essential for vital functions
    • Continues as spinal cord inferiorly
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22
Q

Describe the cross-sectional anatomy of the brain

Gray and white matter

A
  • Gray matter
    • Outer surface of cerebrum
    • Nuclei: neuronal soma
  • White matter
    • Bundle of axons
    • Connects brain to spinal cord
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23
Q

What are the meninges in the brain?

A
  • Protective membranes
  • Dura mater
    • Dense fibrous connective tissue
    • Periosteal: attached to cranial bones
    • Meningeal: inner layer
    • Falx: inner foldgins
  • Dural sinuses
    • Space between dural tissue
    • Collects blood and empties into veins
  • Arachnoid mater
    • Looser
    • Space filled by CSF (shock absorbance)
  • Pia mater
    • Inner layer covering cerebrum
    • Delicate, transparent
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24
Q

Describe the ventricular system of the brain

A
  • Lateral
    • 2 in each cerebral hemisphere
  • Third
    • Connected to lateral
    • Via ventricular foramen
  • Fourth
    • Connected to third
    • Via cerebral aquedect
    • Continues as central canal in spinal cord
  • Choroid Plexus
    • Produces CSF
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25
Q

What are the functions of cerebrospinal fluid?

A
  • Provide buoyancy: prevent brain from collapse
  • Protection: prevent from striking cranium
  • Chemical stability: remove metabolic wastes
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26
Q

What is the brain barrier system?

A
  • Blood-brain barrier: Astrocytes contact blood capillaries, stimulate tight junctions between endothelial cells
  • Blood CSF barrier: formed at choroid plexus
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27
Q

Describe the functions of medulla oblongata (the most inferior part of the brainstem)

A
  • Contains all nerve fibres between brain and spinal cord
  • Four pairs of cranial nerves
  • Cardiac center: regulate heartbeat rate and force
  • Vasomotor center: regulate BP and vasoconstriction
  • Respiratory center: regulate breathing rate and depth
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28
Q

Describe the appearance of the medulla oblongata (the most inferior part of the brainstem)

A
  • Surface
    • Pyramids: clublike ridges
    • Separated by anterior median fissure
  • Internal
    • Ascending and descending tracts
    • Nucleus
    • Fourth ventricle
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29
Q

Describe the features of the pons

A
  • Rostral to the medulla
  • Cerebellar peduncles: connected to cerebellum
  • Four pairs of cranial nerves begin/end
  • Internal structures
    • Ascending and descending tracts
    • Part of fourth ventricle
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30
Q

Describe the features of the midbrain

A
  • Superior to the pons
  • Cerebral aqueduct passes through
  • Colliculus (bumps)
    • Superior: visual reflex (blinking) and visual attention (tracking movement)
    • Inferior: auditory reflexes (startle reflex)
  • Internal structures
    • Ascending and descending tracts
    • Central gray: pain awareness
    • Substantia nigra: motor center, suppress unwanted motor action
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31
Q

Describe the appearance of the cerebellum

A
  • Two hemispheres connected by vermis (narrow wormlike bridge)
  • Folia: gyrus
  • Connect to
    • Medulla via inferior peduncles
    • Pons via middle peduncles
    • Midbrain via superior peduncles
  • Internal structures
    • Arbor vitae: white matter
    • Neurons: Granule cells and Purkinje cells
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32
Q

Describe the functions of the cerebellum

A
  • Motor coordination center
    • Learning motor skills
    • Maintain muscle tone and posture
    • Coordinate eye and body movement
    • Coordinate complex action
  • Receives info from cerebrum and joints
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33
Q

What is reticular formation?

A
  • Loosely organized gray matter
  • Runs vertically thru brainstem
  • Functions
    • Somatic motor control
    • Cardiovascular control
    • Pain modulation
    • Sleep and consciousness
    • Habituation: ignore repetitive stimuli
34
Q

What is diencephalon (the most rostral part of the brainstem)?

A
  • Part of the brainstem and forebrain
  • Thalamus
    • Gateway to cerebral cortex (sensory input)
    • Relays signals from cerebellum to cerebrum
  • Hypothalamus
    • Connected to thalamus via infundibulum
    • Regulates endocrine and autonomic nervous system
    • Influence brainstem functions
    • Thermoregulation, appetite, emotion
  • Epithalamus
    • Pineal gland secretes melatonin
    • Habenula
35
Q

Describe the surface anatomy of the cerebrum

A
  • Extensive folding of gyri to increase SA for housing neurons
  • Frontal lobe: anterior and superior parts
  • Parietal lobe: separated from frontal by central sulcus
  • Occipital lobe: caudal, separated from parietal by parieto-occipital sulcus
  • Temporal lobe: lateral, separated from parietal by lateral sulcus
  • Insula: deep to the lateral sulcus
36
Q

Describe the functions of the five cerebrum lobs

A
  • Frontal: higher cognitive functions
  • Parietal: sensation
  • Occipital: vision
  • Temporal: hearing, smell
  • Insula: taste, visceral sensation
37
Q

What are the white matter in cerebrum?

A
  • Projection tracts: extend vertically between brain and spinal cord centres
  • Commissural tracts: cross horizontally between hemispheres
  • Association tracts: connect regions in the same hemisphere
38
Q

What is the limbic system (sub-system) in the cerebrum?

A
  • Hippocampus
  • Amygdala
    • Input from vision, taste, smell
    • Associate sensation to emotions
    • Sense of fear
  • Cingulate gyrus
39
Q

What is basal nuclei (sub-system) in the cerebrum?

A
  • Lateral to thalamus
  • Involved in motor control (work with cerebellum)
  • Sends feedback of action to motor cortex
40
Q

Describe the higher functions and structures of the cerebrum

A
  • Primary cortex
    • Connect directly with sensory or motor neurons
    • eg with third-order neurons
  • Association cortex
    • Involved in integrative functions
    • eg interpreting sensory input
41
Q

Describe the general/somastosensory senses

A
  • Skin receptors receive general senses, eg touch, pressure, temperature
  • Relayed to association cortex for intepretation
  • Sensory homunculus
    • more cortex area for a body part, more innervated and sensitive
    • eg hand is more sensitive than lower limbs
42
Q

Describe motor control

A
  • Motor association area: Where intention to move begins
  • Neurons: Compile a program for muscle movement, transmitted to primary motor area/precentral gyrus
  • Brainstem and spinal cord: Where motor commands are sent to be carried out
  • Motor homunculus
    • more motor action cortex for a body part, more complex movement
43
Q

What is language function in terms of the nervous system?

A
  • Wernicke system
    • Sensory association
    • Auditory, visual, and sense information
    • Recognition of spoken and written language
  • Broca area
    • Motor association
    • Motor program for related muscles
    • Tranduce signals to primary motor cortex
44
Q

What is the order of the cranial nerves?

A
  1. Olfactory (Oh)
  2. Optic (Once)
  3. Oculomotor (One)
  4. Trochlear (Takes)
  5. Trigeminal (The)
  6. Abducens (Anatomy)
  7. Facial (Final)
  8. Vestibulocochlear (Very)
  9. Glossopharyngeal (Good)
  10. Vagus (Vacation)
  11. Accessory (A-)
  12. Hypoglossal (Head)
45
Q

What are the sensory cranial nerves?

A
  • Olfactory nerve (I)
    • Olfactory receptors
    • For sense of smell
    • Olfactory mucosa to olfactory bulbs
  • Optic nerve (II)
    • For vision
    • Retina to thalamus/midbrain
  • Vestibulocochlear nerve (VIII)
    • For hearing and equilibrium
46
Q

What are the motor cranial nerves?

A
  • Oculomotor nerve (III)
    • Eye movement
    • Midbrain to extra orbital muscles
  • Trochlear nerve (IV)
    • Eye movement
    • Midbrain to superior oblique
  • Abducens nerve (VI)
    • Eye movement
    • Pons to lateral rectus
  • Accessory nerve (XI)
    • Head/neck/shoulder movement
    • Swallowing
  • Hypoglossial nerve (XII)
    • Tongue movement for speech
    • Food manipulation
    • Swallowing
47
Q

What are the mixed cranial nerves (both sensory and motor)?

A
  • Trigeminal nerve (V)
    • VI: General sensation from upper face
    • V2: General sensation from lower face
    • V3: V1, V2, mastication
  • Facial nerve (VII)
    • Sensory: taste
    • Motor: facial expression, secrete tears, saliva, mucus
  • Glossopharyngeal nerve (IX)
    • Sensory: tongue and outer ear
    • Motor: salivation, swallowing, gagging
  • Vagus nerve (X)
    • Sensory: taste, hunger, gastrointestinal discomfort
    • Motor: swallowing, speech, heart rate, broncho constriction
48
Q

What are sensory receptors?

A
  • Structures specialized to detect a stimulus
  • Free nerve endings (simple) or sense organs (complex)
49
Q

What is the classification of receptors based on modality?

A
  • Thermoreceptors: senses heat/cold
  • Photoreceptors: light
  • Chemoreceptors: respond to chemicals eg odor
  • Nociceptors: pain, damage response, excess stimulation
  • Mechanoreceptors: physical deformation
50
Q

What is the classification of receptors based on origin of stimuli?

A
  • Exteroceptors: external to body
  • Interoceptors: internal to body
  • Proprioceptors: position, movement of body parts
51
Q

What are the general senses?

A
  • Simple receptors
  • In skin, muscle, tendon, joint
  • Modalities: touch, pressure, stretch, temperature, pain
52
Q

What are special senses?

A
  • More complex sense organs
  • Modality: vision, hearing and equilibrium, taste and smell
53
Q

What are the unencapsulated receptors for the general senses?

A
  • Dendrites lacking connective tissue wrapping
  • Free nerve endings: Senses hot/cold, pain
  • Tactile discs: Light touch, pressure
  • Hair receptors: Movement, hair bending
54
Q

What are the encapsulated receptors for the general senses?

A
  • Dendrites wrapped in glial cells/connective tissue
  • Tactile corpuscles: Sensitive skin regions eg eyelid
  • End bulbs: Mucous membranes
  • Bulbous corpuscles: Heavy touch, pressure
  • Lamellar corpuscles: Stretch, tickle, vibration
  • Muscle spindles: Muscle tension
  • Tendon organs: Tendon tension
55
Q

What is the receptive field?

A
  • Area supplied by a single sensory neuron
  • Smaller receptive field
    • Higher density of receptors
    • Sensitive to sensation
    • Finer two-point touch discrimination
56
Q

Describe the sensory projection pathway

A
  1. Pain received by Nociceptors
  2. Nerve impulse transduced by first-order neuron
  3. Synapse at gray matter of spinal cord
  4. Second-order neuron sends nerve impulse via axons in ascending tracts
    5.
57
Q

What are the chemical senses?

A
  • Detect environmental changes
  • Gustation (taste): respond to chemicals in food and drinks
  • Olfaction (smell): respond to chemicals in air
58
Q

What are the types of lingual papillae and their functions?

A

Filiform
* Tiny spikes (cat)
* No taste buds
* Sense food texture

Foliate
* Leaf-like
* Degenerates after childhood

Fungiform
* Mushroom-shaped
* Has taste buds

Vallate
* Large
* Back of the tongue
* Has many taste buds

59
Q

What are the anatomical features allowing gustation?

A

Lingual papillae
* Visible bumps on tongue

Taste buds
* Clustered in lingual papillae
* Found on tongue, and oral cavity (cheeks
and soft palate, pharynx and epiglottis)

Taste cells (sensory cells)
* Clustered in taste buds
* Respond to chemicals

60
Q

Describe the features of taste buds

A
  • Sense organ for gustation
  • Taste cells
    • Receptor surfaces for taste molecules
    • Epithelial cells
    • Synapse with nerve fibers
    • Lives for 7-10 days
  • Basal cells
    • Stem cells to replace taste cells
  • Supporting cells
    • Unclear role
61
Q

What cranial nerves are involved in gustation?

A
  • CN VII (Facial Nerve): Anterior 2/3 of the tongue
  • CN IX (Glossopharyngeal Nerve): Posterior 1/3 of the tongue
  • CN X (Vagus Nerve): Taste buds of the palate and pharynx
62
Q

Where are sensory signals sent to?

A
  1. Medulla
  2. Limbic system: Hypothalamus and amygdala (autonomic reflexes)
  3. Thalamus and insula (interpret taste)
63
Q

How is olfaction processed?

A
  1. Airborne chemicals detected by olfactory receptor cells in olfactory mucosa
  2. Receptor cells send signals to glomeruli in the olfactory bulb
  3. Signals transmitted via mitral and tufted cells to the brain (olfactory tract)
  4. Direct pathway to the primary olfactory cortex without thalamic relay
64
Q

Describe the features of receptor cells in the olfactory mucosa

A
  • Directly exposed to the external environment
  • Lives for about 60 days
  • Replaced by basal stem cells
  • Has cilia (olfactory hairs) with olfactory receptors
  • CN I: collection of axons of receptor cells
65
Q

What are the sections of the ear and their functions?

A
  • Outer Ear: Conducts sound to the inner ear
  • Middle Ear: Contains auditory ossicles that amplify sound
  • Inner Ear: Contains the cochlea (hearing) and vestibular apparatus (equilibrium)
66
Q

What are the main parts of the outer ear?

A
  • Auricle (Pinna)
    • Elastic cartilage
    • Directs sound waves into the ear.
  • Auditory Canal (External Acoustic Meatus):
    • Carries sound to the eardrum
    • Lined with skin, tiny hairs and earwax
  • Tympanic Membrane (Eardrum)
    • Thin membrane
    • Separates the outer ear from the middle ear
    • Turns sound waves into vibrations
67
Q

How is the outer ear protected?

A
  • Guard Hairs: Prevent dirt and small objects from getting inside
  • Cerumen (Earwax): Keeps the canal moist and fights germs, debris
68
Q

What are the main parts of the middle ear?

A
  • Tympanic Membrane (Eardrum)
    • Thin membrane
    • Separates the outer ear from the middle ear
    • Vibrates when sound hits it.
  • Ossicles
    • Malleus (Hammer): Attached to the eardrum
    • Incus (Anvil): In between
    • Stapes (Stirrup): Connects to the inner ear
  • Auditory Tube (Eustachian Tube)
    • Connects middle ear to the throat
    • Balances pressure
69
Q

What are the main parts of the inner ear?

A
  • Housed in bony labyrinth of cranium
  • Membranous labyrinth in bony labyrinth
  • Begins at oval window, lead to
    • Vestibule
    • Semicircular canals
    • Cochlea
70
Q

What is the function of the cochlea?

A
  • Sense organ for hearing
  • Spiral organ in cochlear duct
  • Converts sound vibrations into nerve signals via hair cells
71
Q

What are the parts of the Spiral Organ?

A
  • Hair Cells
    • Sensory cells that detect sound vibrations
    • Stereocilia
  • Tectorial Membrane
    • Gel-like structure
    • Covers stereocilia
    • Moves when sound vibrations occur, causing the hair cells to bend
72
Q

Describe how sound detection works (function of stereocilia)

A
  1. Sound waves
  2. Tympanic membrane vibrates
  3. Ossicles amplify vibration
  4. Cochlear fluid vibrates
  5. Bends hair cells/stereocilia
  6. Opens ion channels (potassium)
  7. Depolarization + Releases neurotransmitter
  8. Generates nerve signals
73
Q

What are the Saccule and Utricle and its functions?

A
  • Sensory organs of the inner ear
  • Help detect balance and head position
  • Macula: hair cells and supporting cells
    • Macula sacculi: detects vertical movement (up and down)
    • Macula utriculi: detects horizontal movement (side to side)
      1. Movement of head
      2. Move otolithic membrane
      3. Bends stereocilia
      4. Generates nerve signals
      5. Interpret head orientation by combining signals from saccule and utricle
74
Q

What are Semicircular Ducts?

A
  • Sensory organs of the inner ear
  • Three fluid-filled tubes (endolymph)
  • Ampulla: hair cells and supporting cells
    1. Head turns
    2. Semicircular ducts rotate
    3. Endolymph lags behind
    4. Push cupula
    5. Bends stereocilia
    6. Stimulates hair cells
    7. Sends nerve signals to the cranial nerve
75
Q

What are the accessory structures of the orbit?

A
  • Eyebrows
    • Shield the eyes from glare and perspiration
  • Eyelashes
    • Protective guard hairs
  • Eyelid
    • Moisten eyes
    • Block foreign objects
  • Tarsal plate
    • Maintains eye shape
  • Tarsal glands
    • Oily secretions
    • Prevent tear evaporation
  • Conjunctiva
    • Mucous membrane
    • Covers inner eyelid and anterior eyeball
    • Prevent eyeball from drying
  • Lacrimal apparatus
    • Produces and drains tears into nasal cavity
76
Q

What is the path of tear flow?

A
  1. Lacrimal gland secretes tears
  2. Conjuctiva cleans and lubricates
  3. Drains through the lacrimal curuncle
  4. Into the lacrimal puncta
  5. Lacrimal canaliculus
  6. Lacrimal sac
  7. Nasolacrimal duct
  8. Nasal cavity
77
Q

What are the extrinsic muscles?

A
  • Muscles that control eye movement
  • Rectus Muscles: Superior, inferior, medial, lateral (move in straight directions).
  • Oblique Muscles: Superior and inferior (rotation)
78
Q

What are the components of the eye?

A
  • Three Layers (Tunics)
    • Outer: Sclera, cornea
    • Middle: Choroid, ciliary body, iris
    • Inner: Retina
  • Optical Components
    • Cornea: Admits light
    • Aqueous humor
    • Lens: Focuses image
    • Vitreous body: Maintain intraocular pressure
  • Neural Components
    • Retina and optic nerve
    • Responsible for signal transduction
79
Q

Describe the retina in detail

A
  • Function: Converts light into electrical signals
  • Photoreceptor Cells
    • Rods: Night, monochromatic vision
    • Cones: Day, trichromatic vision
  • Pigment Epithelium
    • Absorbs stray light
    • Supports photoreceptor cells.
  • Neural Layers
    • Bipolar cells
    • Ganglion cells
    • Amacrine cells
    • Horizontal cells
    • Muller glial cells
80
Q

Describe the visual projection pathway

A
  1. First-order neuron: bipolar cells
  2. Second-order neuron: retinal ganglion cells
  3. Axons of ganglion cells form optic nerve
  4. Form optic chiasm with hemidecussation
  5. Most axons from optic tract end at the thalamus
  6. Synapse with third-order neuron
  7. Third-order neurons form the optic radiation
  8. Project to the primary visual cortex
  9. Melanopsin-containing ganglion cells: to pretectal nucleus and superior colliculus, for visual reflex
81
Q

What is the role of the autonomic nervous system (ANS)?

A
  • Regulates involuntary bodily functions
  • Eg heart rate, blood pressure, digestion, and temperature
  • Via visceral reflexes
82
Q

What are the two divisions of the ANS?

A
  • Sympathetic: “fight-or-flight” responses
  • Parasympathetic: “rest and digest” activities, conserving energy

24-25 HUMAN ANATOMY (7 decks)

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