Ch. 14 The Somatic Nervous System and Special Senses.
Ganglia associated with efferent nerve fibers mostly 1. autonomic motor neurons
contain cell bodies of: Ex: Ganglia are collections of neuron cell bodies located in the PNS, and they
1. autonomic motor neurons appear along the autonomic motor pathway.
2. somatic motor neurons The autonomic motor pathway has two neurons in series, a preganglionic and
3. somatic sensory neurons a postganglionic neuron, and the ganglion is where their synapse occurs.
4. autonomic sensory neurons Memory Trick: “Auto = two; Soma = solo.”
Autonomic = 2 neurons (has ganglion).
Somatic = 1 neuron (no ganglion).
Recall: Motor does things, efferent exist to do things.
Which of the following would be stimulated when sound Mechanoreceptors
waves vibrate receptors in the inner ear? Ex: Hearing depends on mechanoreceptors in the cochlea of the inner ear. These
1. Proprioceptors specialized receptors detect mechanical movement, in this case, the vibration of
2. Photoreceptors sound waves, and convert them into nerve impulses that the brain interprets as
3. Mechanoreceptors sound.
4. Chemoreceptors Think: “Mechanoreceptors move.” Anything that involves pressure, stretch, or
5. Thermoreceptors vibration, like hearing or touch uses mechanoreceptors. Think: (Mechanical
recpectors)
Which cranial nerve, if injured or inflamed, would impair 2. IX — Glossopharyngeal nerve
swallowing and taste? Ex: The glossopharyngeal nerve (cranial nerve IX) is responsible for both taste
1. XI sensations from the back (posterior third) of the tongue and helping with
2. IX the muscles involved in swallowing. If this nerve is injured or inflamed,
3. VI both taste and swallowing would be affected.
4. IV Think: “Gloss = tongue, Pharyngeal = throat.
”So cranial nerve IX connects tongue + throat → taste + swallowing.
Peripheral nervous system is subdivided into two divisions. 1. somatic nervous system.
What are they? 2. autonomic nervous system.
The chief difference between the somatic and autonomic B. The number of motor neurons in the pathway.
motor pathways is: Ex:
A) The type of muscles they control Somatic = 1 neuron (direct, like a boss giving orders straight to the worker).
B) The number of motor neurons in the pathway Autonomic = 2 neurons (like a manager and an assistant before reaching the target
C) The number of sensory neurons involved organ).
D) Whether you can win a dance-off with them
In the somatic nervous system, one motor neuron C. Skeletal muscle.
extends from the spinal cord to the: Ex: Somatic = skeletal. Think “Soma = body”, your voluntary muscles.
A) Smooth muscle
B) Glands
C) Skeletal muscle
D) Cardiac muscle
The autonomic nervous system (ANS) controls: C. Involuntary internal organ functions.
A) Skeletal muscle activity Ex: “Auto” means automatic, it keeps your heart beating, lungs breathing, and
B) Voluntary movement stomach digesting even when you forget breakfast.
C) Involuntary internal organ functions Think: It's something that just happens, you don't think about it.
D) Eye-hand coordination
The pre-ganglionic neuron is the one that: A. Comes before the ganglion.
A) Comes before the ganglion Ex: Prefix “pre” = before. It’s the first in line, delivering the signal to the ganglion’s
B) Comes after the ganglion “waiting room.”
C) Bypasses the ganglion
D) Goes on strike before the ganglion
, Ch. 14 The Somatic Nervous System and Special Senses.
The post-ganglionic neuron is the one that: B. Comes after the ganglion.
A) Comes before the ganglion Ex: “Post” = after. It leaves the ganglion and heads straight for the target organ
B) Comes after the ganglion
C) Sends signals to the brain
D) Skips synapses entirely
A ganglion is best described as: B. A collection of neuron cell bodies in the peripheral nervous system (PNS).
A) A group of muscles Ex: Ganglia = “neuron neighborhoods.” Think of them as little nerve cul-de-sacs full
B) A collection of neuron cell bodies in the PNS of cell bodies gossiping about impulses.
C) A bundle of axons in the CNS
D) The name of a heavy-metal band
Sensory neurons - receive - direct, have no time to delay, Sensory neurons - receive - direct, have no time to delay, have to carry the news it
have to carry the news it received as fast as possible TO received as fast as possible TO the CNS news station.
the CNS news station.
Somatic motor neuron - skeletal muscles - goes straight to Somatic motor neuron - skeletal muscles - goes straight to the Penis (PNS), have to
the Penis (PNS), have to cause a rise immediately. cause a rise immediately FROM the CNS.
Autonomic motor neuron - (Smooth muscle, cardiac
muscles, glands) - stops to synapse from CNS to PNS. Autonomic motor neuron - (Smooth muscle, cardiac muscles, glands) - stops to
synapse from CNS to PNS.
Which system is entirely voluntary? A. Somatic nervous system.
A) Somatic nervous system Ex: “Soma” = body, and you move your body on purpose (unless your coffee hasn’t
B) Autonomic nervous system kicked in).
C) Sympathetic division (Remember the Sympathetic division and Parasympathetic division are subdivision
D) Parasympathetic division of autonomic)
Think: Just like somatic exercises, you don't have to do them, they are voluntary.
Motor neuron #1 does NOT synapse directly with target Motor neuron #1 does NOT synapse directly with target effectors (smooth muscle,
effectors (smooth muscle, cardiac muscle and glandular cardiac muscle and glandular tissue), instead, they use there an intervening motor
tissue), instead, they use there an intervening motor neuron.
neuron.
The central nervous system (CNS) consists of the Brain and spinal cord.
________ and the ________. Ex: Central = command center. If your body were Wi-Fi, the CNS would be the
router.
Think: What's down middle?
The peripheral nervous system (PNS) consists of all Cranial and spinal nerves.
________ and ________ nerves. Ex: “Peripheral” = just on the edge of your sight.
A neuron that synapses directly with skeletal muscle must A. Somatic motor pathway.
belong to the: Ex: Only somatic neurons have the VIP pass straight to skeletal muscles, no middle
A) Somatic motor pathway management required.
B) Autonomic motor pathway
C) Sensory division
D) Sympathetic division
, Ch. 14 The Somatic Nervous System and Special Senses.
Which of the following statements is false? C. Autonomic ganglia contain neuron cell bodies in the CNS.
A) Autonomic motor neurons always use two neurons in Ex: Ganglia are outside the CNS, they’re the PNS’s hangout spots. That’s
series a trap question.
B) Somatic motor neurons use one neuron in series
C) Autonomic ganglia contain neuron cell bodies in the
CNS
D) Somatic motor pathways control voluntary movement
Memory Tip: Memory Tip:
S-S Rule: Somatic = Skeletal = Single neuron = voluntary S-S Rule: Somatic = Skeletal = Single neuron = voluntary control.
control. A-A Rule: Autonomic = Automatic = Two neurons = involuntary control.
A-A Rule: Autonomic = Automatic = Two neurons =
involuntary control.
Your somatic system is like you texting your muscles Your somatic system is like you texting your muscles directly: “Move!”
directly: “Move!” Your autonomic system is like your subconscious Siri running background apps —
Your autonomic system is like your subconscious Siri heartbeat, digestion, tears when you lose Wi-Fi.
running background apps, heartbeat, digestion, tears when
you lose Wi-Fi.
A patient suffers nerve damage that affects involuntary Autonomic nervous system.
control of her heart rate and digestion, but her ability to Ex: Heart + digestion = involuntary. That’s 100% the autonomic team’s department.
move her arms and legs voluntarily is normal. Which
division of the nervous system is likely affected?
Compare the somatic and autonomic nervous systems in The somatic system uses one motor neuron to control voluntary skeletal muscles,
one sentence. while the autonomic system uses two motor neurons (pre and post-ganglionic) to
control involuntary smooth, cardiac, and glandular tissue.
Ex: Somatic = single & voluntary; Autonomic = double & automatic.
The somatic nervous system primarily controls: C. Skeletal muscle.
A) Cardiac muscle Ex: “Soma” means body, the somatic system runs your voluntary muscle
B) Smooth muscle movements (like waving, dancing, or slapping your alarm clock).
C) Skeletal muscle
D) Glandular tissue
The target effectors of the somatic nervous system are: B. Skeletal muscle cells.
A) Glands and smooth muscles Ex: The somatic nervous system says, “Move your body!” while the autonomic
B) Skeletal muscle cells system says, “I’ll handle breathing while you panic.”
C) The heart and lungs
D) Digestive organs
Which statement about reflex arcs is TRUE? C. They are rapid, involuntary responses coordinated by the spinal cord.
A) They require the brain to make the final decision. Ex: Reflexes are like your body’s “auto-reply” feature, quick, automatic, and
B) They are slow because the signal must go to the occasionally dramatic (like jerking your hand from a hot stove).
cerebrum.
C) They are rapid, involuntary responses coordinated by
the spinal cord.
D) They only occur when you think about moving.
The neurotransmitter released at the neuromuscular C. Acetylcholine.
junction of the somatic nervous system is: Ex: Acetylcholine (ACh) is the “spark plug” that tells muscles, “Let’s move!” without
A) Epinephrine it, you’re just flexing your imagination.
B) Norepinephrine
C) Acetylcholine
D) Dopamine
The neuromuscular junction is classified as what type of C. Chemical synapse.
synapse? Ex: It’s chemical because neurotransmitters (ACh) do the talking, like molecules
A) Electrical synapse gossiping across the synaptic gap.
B) Mechanical synapse
C) Chemical synapse
D) Reflexive synapse
, Ch. 14 The Somatic Nervous System and Special Senses.
The spinal cord rather than the brain controls most C. Reflexes must occur rapidly to protect the body.
reflexes because: Ex: The spinal cord says, “No time to consult the boss!” and acts before your brain
A) Reflexes are too slow for the brain to handle. even knows what’s happening.
B) The brain doesn’t have pain receptors.
C) Reflexes must occur rapidly to protect the body.
D) The brain refuses to multitask.
The somatic motor pathway differs from the autonomic B. Uses one single motor neuron with no intervening synapses.
pathway because it: Ex: Somatic = single line of command. Like sending a direct text, no middle
A) Uses two motor neurons manager forwarding the message.
B) Uses one single motor neuron with no intervening
synapses
C) Always involves a ganglion
D) Has both pre- and post-ganglionic neurons
The neurotransmitter released at the neuromuscular Acetylcholine.
junction is ________. Ex: ACh = “Action Chemical.” When it drops, muscles pop (contract)!
A reflex arc is an involuntary, automatic response to a Spinal cord.
stimulus that is coordinated by the ________. Ex: Think of the spinal cord as your “reflex headquarters.” It acts so fast, the brain
finds out after the action, like, “Wait… did we just touch fire?”
The signal in a reflex arc travels from the receptor to the Dorsal root; ventral root.
CNS via the ________ root and exits via the ________ Ex: Dorsal = in, Ventral = out.
root. Think:
“Dorsal brings data in, Eating
Ventral sends vibes out. Pooping
A student accidentally touches a hot stove and instantly The spinal cord.
pulls their hand away before realizing it. Which structure Ex: The spinal cord doesn’t wait for permission, it’s the overachiever of the nervous
processed the reflex? system. “Ouch first, think later.”
During a checkup, a doctor taps your knee with a small Somatic reflex.
hammer and your leg kicks out involuntarily. This reaction Ex: Classic spinal reflex. Your doctor’s testing your nerves, literally.
is an example of a:
The somatic nervous system controls voluntary skeletal The somatic nervous system controls voluntary skeletal movements and involuntary
movements and involuntary reflex arcs, which are reflex arcs, which are automatic, rapid responses coordinated by the spinal cord
automatic, rapid responses coordinated by the spinal cord before impulses reach the brain.
before impulses reach the brain.
In the reflex arc pathway, the interneuron's main role is to: Process the incoming sensory signal and relay an outgoing motor response.
Ex: The interneuron is like the office manager, gets the message in, sends
instructions out.
Analogy: Analogy:
Reflexes are your body’s “customer service hotline.” Reflexes are your body’s “customer service hotline.”
Receptor = the customer (ouch, that’s hot!) Receptor = the customer (ouch, that’s hot!)
Spinal cord = the rep (“We’re on it!”) Spinal cord = the rep (“We’re on it!”)
Motor neuron = the technician (jerks hand away). Motor neuron = the technician (jerks hand away).
Ganglia associated with efferent nerve fibers mostly 1. autonomic motor neurons
contain cell bodies of: Ex: Ganglia are collections of neuron cell bodies located in the PNS, and they
1. autonomic motor neurons appear along the autonomic motor pathway.
2. somatic motor neurons The autonomic motor pathway has two neurons in series, a preganglionic and
3. somatic sensory neurons a postganglionic neuron, and the ganglion is where their synapse occurs.
4. autonomic sensory neurons Memory Trick: “Auto = two; Soma = solo.”
Autonomic = 2 neurons (has ganglion).
Somatic = 1 neuron (no ganglion).
Recall: Motor does things, efferent exist to do things.
Which of the following would be stimulated when sound Mechanoreceptors
waves vibrate receptors in the inner ear? Ex: Hearing depends on mechanoreceptors in the cochlea of the inner ear. These
1. Proprioceptors specialized receptors detect mechanical movement, in this case, the vibration of
2. Photoreceptors sound waves, and convert them into nerve impulses that the brain interprets as
3. Mechanoreceptors sound.
4. Chemoreceptors Think: “Mechanoreceptors move.” Anything that involves pressure, stretch, or
5. Thermoreceptors vibration, like hearing or touch uses mechanoreceptors. Think: (Mechanical
recpectors)
Which cranial nerve, if injured or inflamed, would impair 2. IX — Glossopharyngeal nerve
swallowing and taste? Ex: The glossopharyngeal nerve (cranial nerve IX) is responsible for both taste
1. XI sensations from the back (posterior third) of the tongue and helping with
2. IX the muscles involved in swallowing. If this nerve is injured or inflamed,
3. VI both taste and swallowing would be affected.
4. IV Think: “Gloss = tongue, Pharyngeal = throat.
”So cranial nerve IX connects tongue + throat → taste + swallowing.
Peripheral nervous system is subdivided into two divisions. 1. somatic nervous system.
What are they? 2. autonomic nervous system.
The chief difference between the somatic and autonomic B. The number of motor neurons in the pathway.
motor pathways is: Ex:
A) The type of muscles they control Somatic = 1 neuron (direct, like a boss giving orders straight to the worker).
B) The number of motor neurons in the pathway Autonomic = 2 neurons (like a manager and an assistant before reaching the target
C) The number of sensory neurons involved organ).
D) Whether you can win a dance-off with them
In the somatic nervous system, one motor neuron C. Skeletal muscle.
extends from the spinal cord to the: Ex: Somatic = skeletal. Think “Soma = body”, your voluntary muscles.
A) Smooth muscle
B) Glands
C) Skeletal muscle
D) Cardiac muscle
The autonomic nervous system (ANS) controls: C. Involuntary internal organ functions.
A) Skeletal muscle activity Ex: “Auto” means automatic, it keeps your heart beating, lungs breathing, and
B) Voluntary movement stomach digesting even when you forget breakfast.
C) Involuntary internal organ functions Think: It's something that just happens, you don't think about it.
D) Eye-hand coordination
The pre-ganglionic neuron is the one that: A. Comes before the ganglion.
A) Comes before the ganglion Ex: Prefix “pre” = before. It’s the first in line, delivering the signal to the ganglion’s
B) Comes after the ganglion “waiting room.”
C) Bypasses the ganglion
D) Goes on strike before the ganglion
, Ch. 14 The Somatic Nervous System and Special Senses.
The post-ganglionic neuron is the one that: B. Comes after the ganglion.
A) Comes before the ganglion Ex: “Post” = after. It leaves the ganglion and heads straight for the target organ
B) Comes after the ganglion
C) Sends signals to the brain
D) Skips synapses entirely
A ganglion is best described as: B. A collection of neuron cell bodies in the peripheral nervous system (PNS).
A) A group of muscles Ex: Ganglia = “neuron neighborhoods.” Think of them as little nerve cul-de-sacs full
B) A collection of neuron cell bodies in the PNS of cell bodies gossiping about impulses.
C) A bundle of axons in the CNS
D) The name of a heavy-metal band
Sensory neurons - receive - direct, have no time to delay, Sensory neurons - receive - direct, have no time to delay, have to carry the news it
have to carry the news it received as fast as possible TO received as fast as possible TO the CNS news station.
the CNS news station.
Somatic motor neuron - skeletal muscles - goes straight to Somatic motor neuron - skeletal muscles - goes straight to the Penis (PNS), have to
the Penis (PNS), have to cause a rise immediately. cause a rise immediately FROM the CNS.
Autonomic motor neuron - (Smooth muscle, cardiac
muscles, glands) - stops to synapse from CNS to PNS. Autonomic motor neuron - (Smooth muscle, cardiac muscles, glands) - stops to
synapse from CNS to PNS.
Which system is entirely voluntary? A. Somatic nervous system.
A) Somatic nervous system Ex: “Soma” = body, and you move your body on purpose (unless your coffee hasn’t
B) Autonomic nervous system kicked in).
C) Sympathetic division (Remember the Sympathetic division and Parasympathetic division are subdivision
D) Parasympathetic division of autonomic)
Think: Just like somatic exercises, you don't have to do them, they are voluntary.
Motor neuron #1 does NOT synapse directly with target Motor neuron #1 does NOT synapse directly with target effectors (smooth muscle,
effectors (smooth muscle, cardiac muscle and glandular cardiac muscle and glandular tissue), instead, they use there an intervening motor
tissue), instead, they use there an intervening motor neuron.
neuron.
The central nervous system (CNS) consists of the Brain and spinal cord.
________ and the ________. Ex: Central = command center. If your body were Wi-Fi, the CNS would be the
router.
Think: What's down middle?
The peripheral nervous system (PNS) consists of all Cranial and spinal nerves.
________ and ________ nerves. Ex: “Peripheral” = just on the edge of your sight.
A neuron that synapses directly with skeletal muscle must A. Somatic motor pathway.
belong to the: Ex: Only somatic neurons have the VIP pass straight to skeletal muscles, no middle
A) Somatic motor pathway management required.
B) Autonomic motor pathway
C) Sensory division
D) Sympathetic division
, Ch. 14 The Somatic Nervous System and Special Senses.
Which of the following statements is false? C. Autonomic ganglia contain neuron cell bodies in the CNS.
A) Autonomic motor neurons always use two neurons in Ex: Ganglia are outside the CNS, they’re the PNS’s hangout spots. That’s
series a trap question.
B) Somatic motor neurons use one neuron in series
C) Autonomic ganglia contain neuron cell bodies in the
CNS
D) Somatic motor pathways control voluntary movement
Memory Tip: Memory Tip:
S-S Rule: Somatic = Skeletal = Single neuron = voluntary S-S Rule: Somatic = Skeletal = Single neuron = voluntary control.
control. A-A Rule: Autonomic = Automatic = Two neurons = involuntary control.
A-A Rule: Autonomic = Automatic = Two neurons =
involuntary control.
Your somatic system is like you texting your muscles Your somatic system is like you texting your muscles directly: “Move!”
directly: “Move!” Your autonomic system is like your subconscious Siri running background apps —
Your autonomic system is like your subconscious Siri heartbeat, digestion, tears when you lose Wi-Fi.
running background apps, heartbeat, digestion, tears when
you lose Wi-Fi.
A patient suffers nerve damage that affects involuntary Autonomic nervous system.
control of her heart rate and digestion, but her ability to Ex: Heart + digestion = involuntary. That’s 100% the autonomic team’s department.
move her arms and legs voluntarily is normal. Which
division of the nervous system is likely affected?
Compare the somatic and autonomic nervous systems in The somatic system uses one motor neuron to control voluntary skeletal muscles,
one sentence. while the autonomic system uses two motor neurons (pre and post-ganglionic) to
control involuntary smooth, cardiac, and glandular tissue.
Ex: Somatic = single & voluntary; Autonomic = double & automatic.
The somatic nervous system primarily controls: C. Skeletal muscle.
A) Cardiac muscle Ex: “Soma” means body, the somatic system runs your voluntary muscle
B) Smooth muscle movements (like waving, dancing, or slapping your alarm clock).
C) Skeletal muscle
D) Glandular tissue
The target effectors of the somatic nervous system are: B. Skeletal muscle cells.
A) Glands and smooth muscles Ex: The somatic nervous system says, “Move your body!” while the autonomic
B) Skeletal muscle cells system says, “I’ll handle breathing while you panic.”
C) The heart and lungs
D) Digestive organs
Which statement about reflex arcs is TRUE? C. They are rapid, involuntary responses coordinated by the spinal cord.
A) They require the brain to make the final decision. Ex: Reflexes are like your body’s “auto-reply” feature, quick, automatic, and
B) They are slow because the signal must go to the occasionally dramatic (like jerking your hand from a hot stove).
cerebrum.
C) They are rapid, involuntary responses coordinated by
the spinal cord.
D) They only occur when you think about moving.
The neurotransmitter released at the neuromuscular C. Acetylcholine.
junction of the somatic nervous system is: Ex: Acetylcholine (ACh) is the “spark plug” that tells muscles, “Let’s move!” without
A) Epinephrine it, you’re just flexing your imagination.
B) Norepinephrine
C) Acetylcholine
D) Dopamine
The neuromuscular junction is classified as what type of C. Chemical synapse.
synapse? Ex: It’s chemical because neurotransmitters (ACh) do the talking, like molecules
A) Electrical synapse gossiping across the synaptic gap.
B) Mechanical synapse
C) Chemical synapse
D) Reflexive synapse
, Ch. 14 The Somatic Nervous System and Special Senses.
The spinal cord rather than the brain controls most C. Reflexes must occur rapidly to protect the body.
reflexes because: Ex: The spinal cord says, “No time to consult the boss!” and acts before your brain
A) Reflexes are too slow for the brain to handle. even knows what’s happening.
B) The brain doesn’t have pain receptors.
C) Reflexes must occur rapidly to protect the body.
D) The brain refuses to multitask.
The somatic motor pathway differs from the autonomic B. Uses one single motor neuron with no intervening synapses.
pathway because it: Ex: Somatic = single line of command. Like sending a direct text, no middle
A) Uses two motor neurons manager forwarding the message.
B) Uses one single motor neuron with no intervening
synapses
C) Always involves a ganglion
D) Has both pre- and post-ganglionic neurons
The neurotransmitter released at the neuromuscular Acetylcholine.
junction is ________. Ex: ACh = “Action Chemical.” When it drops, muscles pop (contract)!
A reflex arc is an involuntary, automatic response to a Spinal cord.
stimulus that is coordinated by the ________. Ex: Think of the spinal cord as your “reflex headquarters.” It acts so fast, the brain
finds out after the action, like, “Wait… did we just touch fire?”
The signal in a reflex arc travels from the receptor to the Dorsal root; ventral root.
CNS via the ________ root and exits via the ________ Ex: Dorsal = in, Ventral = out.
root. Think:
“Dorsal brings data in, Eating
Ventral sends vibes out. Pooping
A student accidentally touches a hot stove and instantly The spinal cord.
pulls their hand away before realizing it. Which structure Ex: The spinal cord doesn’t wait for permission, it’s the overachiever of the nervous
processed the reflex? system. “Ouch first, think later.”
During a checkup, a doctor taps your knee with a small Somatic reflex.
hammer and your leg kicks out involuntarily. This reaction Ex: Classic spinal reflex. Your doctor’s testing your nerves, literally.
is an example of a:
The somatic nervous system controls voluntary skeletal The somatic nervous system controls voluntary skeletal movements and involuntary
movements and involuntary reflex arcs, which are reflex arcs, which are automatic, rapid responses coordinated by the spinal cord
automatic, rapid responses coordinated by the spinal cord before impulses reach the brain.
before impulses reach the brain.
In the reflex arc pathway, the interneuron's main role is to: Process the incoming sensory signal and relay an outgoing motor response.
Ex: The interneuron is like the office manager, gets the message in, sends
instructions out.
Analogy: Analogy:
Reflexes are your body’s “customer service hotline.” Reflexes are your body’s “customer service hotline.”
Receptor = the customer (ouch, that’s hot!) Receptor = the customer (ouch, that’s hot!)
Spinal cord = the rep (“We’re on it!”) Spinal cord = the rep (“We’re on it!”)
Motor neuron = the technician (jerks hand away). Motor neuron = the technician (jerks hand away).
