Neu Quiz Autonomic Nervous System Flashcards
Autonomic Nervous System Overview
CNS - PNS - sensory afferent division or motor efferent division - after motor somatic or autonomic - from autonomic sympathetic or parasympathetic
Efferent - from brain to body
CNS and PNS
Central nervous system (CNS): Brain and spinal cord Integrative and control centers
Peripheral nervous system (PNS): Cranial nerves and spinal nerves + Communication lines between the CNS and the rest of the body
Somatic Nervous System:
Somatic motor (voluntary) and Conducts impulses from the CNS to skeletal muscles and is myelinated
Autonomic Nervous System + Two Types:
Visceral motor (involuntary) and Conducts impulses from the CNS to cardiac muscles, smooth Visceral sensory fiber muscles, and glands; not myelinated
Two Types: sympathetic (Mobilizes body systems during activity, ganglion lie just outside spinal cord on both sides) and parasympathetic (Conserves energy Promotes housekeeping functions during rest) - both can innervate the same organ but typically have opposite effects in end organ
Autonomic Nervous System (ANS) In Depth:
ANS consists of motor neurons that Innervate: smooth muscle(gi tract), cardiac muscle, and glands(addrenal, pancreas, gallbladder)
Make adjustments to maintain internal homeostasis - balance (controls things like blood pressure, heart rate, body temp, digestion, metabolism, balance, electrolytes, and the production of fluids like urination, defecation, and sex
Operate via subconscious control - INVOLUNTARY
Somatic(skeletal muscle) Versus Autonomic Nervous Systems:
Both have motor fibers
Differ in Effectors - what they innervate(target organ), Efferent pathways and ganglia (travel through different axons and cell bodies), and Target organ responses to neurotransmitters (not always excitatory)
Role of the Parasympathetic Division + Effects of parasympathetic control + NT:
Promotes maintenance activities and conserves body energy(rest and digest)
Effects of parasympathetic control: Heart rate and respiratory rates are low, Gastrointestinal tract activity high, Pupils constricted, Lenses accommodated for close vision, Constricts bronchioles
Ach - nicotinic and Muscarinic (exhibitory and inhibitory)
Role of the Sympathetic Division + NT:
Mobilizes body during activity; “fight-or-flight” system
Exercise, excitement, emergency, embarrassment: Increased heart rate, Dilates bronchioles (lung airways), Increased BP, Dry mouth, Cold, sweaty skin, Dilated pupils(bigger more light enter) (pupil dilate get bigger scared), Liver releases glucose
Ach and norepinephrine
ACh at nicotinic receptors excitatory
Neurotransmitters:
Acetylcholine (ACh): Cholinergic fibers release ACh – All ANS preganglionic axons and All parasympathetic postganglionic axons at effector synapse
Norepinephrine (NE) (Adrenaline): Adrenergic fibers release NE - Most sympathetic postganglionic axons at effector and Exception: sympathetic postganglionic fibers secrete ACh at sweat glands
Pre Gang - Para and Symp are both Ach
Post Gang - Para is Ach and Symp is N.E + E
Cholinergic Receptors:
Receptors for Acetylcholine (ACh) are called cholinergic receptors
TWO TYPES: 1. Nicotinic(inotropic) 2. Muscarinic(metatropic)
Cholinergic: Nicotinic Receptors (inotropic)
Found on Skeletal muscle cells at NMJ (NM type), All ganglionic neurons (sympathetic and parasympathetic) (NN type)
Effect of ACh at nicotinic receptors is always stimulatory
Cholinergic: Muscarinic Receptors
Part of the parasympathetic response and Found on All effector cells (most organs) stimulated by postganglionic cholinergic fibers
Effect of ACh at muscarinic receptors - Can be either inhibitory or excitatory
Adrenergic Receptors (metabotropic) (receptor for NE)
Receptors for Norepinephrine called Adrenergic Receptors – part of the sympathetic response
Found on all effector cells (all organs) stimulated by postganglionic adrenergic fibers (type of adrenergic receptors on each end organ differs)
Two major classes: Alpha and Beta
Adrenergic Receptors - Alpha
Alpha (α) (subtypes α1, α2)
A1 – Blood vessels of skin, mucus membranes, abdominal organs (CONSTRICTS, increase BP)
A2 – adrenergic axon terminals (inhibit release of NE)
Effects of NE depend on which subclass of receptor predominates on target organ
Alpha 1 and Beta 1 – stimulatory (B1 cardiovascular issues)
Alpha 2, Beta, 2, Beta 3 - inhibitory (B2 asthma)
Adrenergic Receptors - Beta
Beta (β) (subtypes β1, β2 , β3)
B1 – HEART, (Increase cardiac output, increase HR)
B2 – Bronchioles and visceral smooth muscle (dilation + G1 activity)
B3 – Fat tissue
Effects of NE depend on which subclass of receptor predominates on target organ
Alpha 1 and Beta 1 – stimulatory (B1 cardiovascular issues)
Alpha 2, Beta, 2, Beta 3 - inhibitory (B2 asthma)
Control of ANS Function
Hypothalamus(fight flight feed reproduction) (part of CNS!) —main integrative center of ANS activity
Centers of hypothalamus control:
- Heart activity and blood pressure
- Body temperature, water balance, homeostasis, and endocrine(hormone) activity
- Reactions to fear and “fight-or-flight” system
- Stress Response
Cerebral input via limbic system on hypothalamic centers (cortical input/modifications of hypothalamic activity)
Amygdala
Hippocampus
Hypothalamus
Basal Ganglia
Cerebellum
Medulla
Cingulate gyrus
Frontal Lobe
Parietal Lobe
Occipital Lobe
Temporal Lobe
Amygdala: processing emotion and threat (“fear center”)
Hippocampus: binding items and events in memory and role in learning
Hypothalamus: fight flight feeding fornication
Basal Ganglia: regulating motor activity and starting/stopping action – includes a number of other functions, specifically reward
Cerebellum: needed for movement coordination and motor control (called little brain)
Medulla: Crucial for regulating breathing, heart rate, etc.
Cingulate gyrus: detecting “conflict” in decision making, regulates aggression, emotional response to pain
Frontal Lobe: primary motor cortex, reasoning, planning, speech, emotions, problem solving, decision making
Parietal Lobe: primary somatosensory cortex(touch mostly), orientation, recognition, attention
Occipital Lobe: visual processing
Temporal Lobe: hearing, smell, memory, and speech
Spinal Cord
Sensory information travels from the periphery to the brain through the dorsal spinal cord (input)
dorsal horn - sensory
Information goes in through dorsal and out through ventral
Ventral horn - motor
Motor information travels from the brain to the periphery through the ventral spinal cord (output)
Dendrites
Axons
Nerve Signal
Neuron Processes:
Make connections between neurons
Two types:
Dendrites – receive input
Branching
Contain neurotransmitter receptors
Axons – transmit signal – carry away from cell body
Secretory region
Release Neurotransmitters extracellular space
Either excite or inhibit the neuron it contacts
Nerve Signal:
Electrical event that travels in 1 direction
Outside signal → dendrites → cell body → axon → axon terminal → synapse → target cells
Which tissue is not innervated by the autonomic nervous
system?
a. Sweat glands
b. Bones
c. Stomach
d. Heart
e. Bladder
b. Bones
The postganglionic sympathetic neuron releases _______ onto
all target organs except _______.
a. acetylcholine; blood vessels
b. norepinephrine; piloerector muscles
c. acetylcholine; heart
d. norepinephrine; sweat glands
d. norepinephrine; sweat glands
For each item, decide whether the sympathetic or parasympathetic
division of the ANS is at work and name the NT and type of receptor
being used.
* Increased food digestion
* Increased heart rate during exercise
* Opening up (dilation) of lung airways
* Pupil dilation when studying for final exam
* Increased urine output
* Respiratory rate slows down
* Blood vessels constrict (blood pressure rises)
Para
Symp
Symp
Symp
Para
Para
Symp
You are soundly sleeping in your home, alone. You wake up to the
sound of someone walking around in your house. Which system is activated by the threat?
What do you expect to happen to your respiratory rate, heart rate
and eyes?
a) Heart rate increases, RR decreases and pupil constricts
b) HR decreases, RR decreases, pupil constricts
c) HR increases, RR increases, pupil dilates
d) HR decreases, RR increases, pupil dilates
c) HR increases, RR increases, pupil dilates
Norepinephrine binds to ____________ receptors and is
_____________.
a. Nicotinic receptors; stimulatory only
b. Muscarinic receptors; stimulatory and inhibitory
c. Adrenergic receptors; stimulatory only
d. Adrenergic receptors; stimulatory and inhibitory
e. Muscarinic receptors; stimulatory only
d. Adrenergic receptors; stimulatory and inhibitory
Which brain area primary controls ANS function?
a. Amygdala
b. Hypothalamus
c. Frontal Lobe
d. Cerebellum
e. Hippocampus
b. Hypothalamus
TJ is a 4 y/o boy who has asthma. When he has an asthma attack, his
airways constrict tightly and he has to take the drug Albuterol to open
them. How do you think Albuterol works (Select all that apply):
a. Activates muscarinic receptors
b. Blocks acetylcholine at the effector organ
c. Activates adrenergic receptors
d. Increases breakdown of acetylcholine from pre-synaptic neurons
e. Activates nicotinic receptors
b. Blocks acetylcholine at the effector organ
c. Activates adrenergic receptors
d. Increases breakdown of acetylcholine from pre-synaptic neurons
TJ is a 4 y/o boy who has asthma. When he has an asthma attack, his
airways constrict tightly and he has to take the drug Albuterol to open
them. Which of the following might be a side effect of this drug, given
that it stimulates adrenergic receptors?
a. Decreased blood pressure
b. Increased digestion
c. Decreased size of pupil
d. Increased heart rate
d. Increased heart rate
A 35 y/o woman is being seen for frequent urge to urinate and an inability to
prevent urination. She is diagnosed with overactive bladder, and her doctor would
like to prescribe her a medication to treat the disorder. What medication would
work best (Select 2)?
a. A drug that activates nicotinic receptors on post-ganglionic neurons
b. A drug that activates adrenergic receptors on the bladder
c. A drug that inhibits muscarinic receptors on the bladder
d. A drug that inhibits adrenergic receptors on the bladder
e. A drug that activates muscarinic receptors on the bladder
f. A drug that inhibits nicotinic receptors on post-ganglionic neuron
b. A drug that activates adrenergic receptors on the bladder
c. A drug that inhibits muscarinic receptors on the bladder
The physician decides on the anti-muscarinic drug, Detrol. This blocks
muscarinic receptors. Which of the following could be possible side
effects?
a. Gastric retention – stomach holds contents longer than normal
b. Decreased breathing rate
c. Decreased blood pressure
d. Constriction of airways
a. Gastric retention – stomach holds contents longer than normal
