Podcast
Questions and Answers
Which of the following accurately describes the sympathetic nervous system?
Which of the following accurately describes the sympathetic nervous system?
Which effector organs are primarily associated with the autonomic motor nervous system?
Which effector organs are primarily associated with the autonomic motor nervous system?
What is a characteristic of the pathways in the autonomic nervous system?
What is a characteristic of the pathways in the autonomic nervous system?
In terms of anatomy, where are the preganglionic cell bodies of the parasympathetic system located?
In terms of anatomy, where are the preganglionic cell bodies of the parasympathetic system located?
Signup and view all the answers
Which of the following statements about the sympathetic nervous system is incorrect?
Which of the following statements about the sympathetic nervous system is incorrect?
Signup and view all the answers
What is the primary function of sympathetic splanchnic nerves?
What is the primary function of sympathetic splanchnic nerves?
Signup and view all the answers
How does the length of postganglionic fibers in the parasympathetic nervous system compare to that in the sympathetic nervous system?
How does the length of postganglionic fibers in the parasympathetic nervous system compare to that in the sympathetic nervous system?
Signup and view all the answers
Which of the following functions is primarily regulated by the parasympathetic nervous system?
Which of the following functions is primarily regulated by the parasympathetic nervous system?
Signup and view all the answers
Which sympathetic pathway directly innervates the adrenal medulla?
Which sympathetic pathway directly innervates the adrenal medulla?
Signup and view all the answers
Where are sympathetic ganglia typically located?
Where are sympathetic ganglia typically located?
Signup and view all the answers
What structure connects spinal nerves to the sympathetic trunk?
What structure connects spinal nerves to the sympathetic trunk?
Signup and view all the answers
Which pair accurately describes the locations of the binding sites for sympathetic and parasympathetic preganglionic fibers?
Which pair accurately describes the locations of the binding sites for sympathetic and parasympathetic preganglionic fibers?
Signup and view all the answers
What effect does sympathetic activation have on heart rate and respiration?
What effect does sympathetic activation have on heart rate and respiration?
Signup and view all the answers
The greater thoracic splanchnic nerve originates from which spinal segments?
The greater thoracic splanchnic nerve originates from which spinal segments?
Signup and view all the answers
Which of the following is NOT a target of postganglionic fibers from the celiac ganglion?
Which of the following is NOT a target of postganglionic fibers from the celiac ganglion?
Signup and view all the answers
Which of the following factors does not differentiate the autonomic nervous system from the somatic nervous system?
Which of the following factors does not differentiate the autonomic nervous system from the somatic nervous system?
Signup and view all the answers
Which type of fibers do gray ramus communicantes carry?
Which type of fibers do gray ramus communicantes carry?
Signup and view all the answers
Which cranial nerve is associated with the lacrimal glands and nasal cavity glands in the parasympathetic system?
Which cranial nerve is associated with the lacrimal glands and nasal cavity glands in the parasympathetic system?
Signup and view all the answers
What is the general activation pattern of the sympathetic nervous system during an emergency situation?
What is the general activation pattern of the sympathetic nervous system during an emergency situation?
Signup and view all the answers
What type of effect do adrenergic receptors commonly have?
What type of effect do adrenergic receptors commonly have?
Signup and view all the answers
Which of the following best describes cholinergic receptors?
Which of the following best describes cholinergic receptors?
Signup and view all the answers
Postganglionic fibers from which ganglion innervate the distal part of the large intestine?
Postganglionic fibers from which ganglion innervate the distal part of the large intestine?
Signup and view all the answers
Which pathway does a sympathetic fiber follow to target abdominal organs without synapsing in the sympathetic trunk ganglion?
Which pathway does a sympathetic fiber follow to target abdominal organs without synapsing in the sympathetic trunk ganglion?
Signup and view all the answers
Which sympathetic ganglion provides fibers to thoracic viscera?
Which sympathetic ganglion provides fibers to thoracic viscera?
Signup and view all the answers
What is the main neurotransmitter released by adrenergic fibers?
What is the main neurotransmitter released by adrenergic fibers?
Signup and view all the answers
Which function distinguishes the adrenal medulla in the autonomic nervous system?
Which function distinguishes the adrenal medulla in the autonomic nervous system?
Signup and view all the answers
Which system is primarily regulated by the hypothalamus in the autonomic nervous system?
Which system is primarily regulated by the hypothalamus in the autonomic nervous system?
Signup and view all the answers
Which fibers carry postganglionic axons from the sympathetic trunk to spinal nerves?
Which fibers carry postganglionic axons from the sympathetic trunk to spinal nerves?
Signup and view all the answers
What is the function of the sympathetic splanchnic nerves?
What is the function of the sympathetic splanchnic nerves?
Signup and view all the answers
Which ganglion synapses with the greater thoracic splanchnic nerve?
Which ganglion synapses with the greater thoracic splanchnic nerve?
Signup and view all the answers
What is the primary role of the sympathetic nervous system during periods of stress or activity?
What is the primary role of the sympathetic nervous system during periods of stress or activity?
Signup and view all the answers
Which anatomical feature differentiates the location of the preganglionic cell bodies in the parasympathetic nervous system from those in the sympathetic nervous system?
Which anatomical feature differentiates the location of the preganglionic cell bodies in the parasympathetic nervous system from those in the sympathetic nervous system?
Signup and view all the answers
Where are the prevertebral ganglia primarily located?
Where are the prevertebral ganglia primarily located?
Signup and view all the answers
What type of neurotransmitter do adrenergic fibers primarily release?
What type of neurotransmitter do adrenergic fibers primarily release?
Signup and view all the answers
What anatomical feature of the sympathetic nervous system allows for mass activation of responses?
What anatomical feature of the sympathetic nervous system allows for mass activation of responses?
Signup and view all the answers
Which structure connects sympathetic trunks with spinal nerves?
Which structure connects sympathetic trunks with spinal nerves?
Signup and view all the answers
Which of the following statements is true about the lengths of preganglionic and postganglionic fibers in the sympathetic nervous system?
Which of the following statements is true about the lengths of preganglionic and postganglionic fibers in the sympathetic nervous system?
Signup and view all the answers
What is the primary role of effector cells with muscarinic receptors?
What is the primary role of effector cells with muscarinic receptors?
Signup and view all the answers
What is a primary function of the parasympathetic nervous system?
What is a primary function of the parasympathetic nervous system?
Signup and view all the answers
Which of the following is a postganglionic target of the inferior mesenteric ganglion?
Which of the following is a postganglionic target of the inferior mesenteric ganglion?
Signup and view all the answers
Which of the following cranial nerves is NOT associated with parasympathetic functions?
Which of the following cranial nerves is NOT associated with parasympathetic functions?
Signup and view all the answers
What type of axon branches does the parasympathetic nervous system typically have?
What type of axon branches does the parasympathetic nervous system typically have?
Signup and view all the answers
What occurs during the activation of adrenergic receptors?
What occurs during the activation of adrenergic receptors?
Signup and view all the answers
Where are the sympathetic ganglia primarily located?
Where are the sympathetic ganglia primarily located?
Signup and view all the answers
Which statement correctly describes a characteristic of cholinergic receptors?
Which statement correctly describes a characteristic of cholinergic receptors?
Signup and view all the answers
Which type of ramus is responsible for carrying preganglionic fibers to the sympathetic trunk?
Which type of ramus is responsible for carrying preganglionic fibers to the sympathetic trunk?
Signup and view all the answers
Which subdivision of the autonomic nervous system is associated with involuntary control of cardiac and smooth muscles?
Which subdivision of the autonomic nervous system is associated with involuntary control of cardiac and smooth muscles?
Signup and view all the answers
Which function is primarily associated with sympathetic splanchnic nerves?
Which function is primarily associated with sympathetic splanchnic nerves?
Signup and view all the answers
Which of the following represents an antagonistic effect of the autonomic nervous systems?
Which of the following represents an antagonistic effect of the autonomic nervous systems?
Signup and view all the answers
What is the primary neurotransmitter synthesized and released by all sympathetic preganglionic fibers?
What is the primary neurotransmitter synthesized and released by all sympathetic preganglionic fibers?
Signup and view all the answers
What characterizes the prevertebral (collateral) ganglia in the sympathetic nervous system?
What characterizes the prevertebral (collateral) ganglia in the sympathetic nervous system?
Signup and view all the answers
In terms of physiological response, how does the parasympathetic nervous system primarily function?
In terms of physiological response, how does the parasympathetic nervous system primarily function?
Signup and view all the answers
Which structure is associated with the fight-or-flight response of the sympathetic nervous system?
Which structure is associated with the fight-or-flight response of the sympathetic nervous system?
Signup and view all the answers
Study Notes
Peripheral Nervous System (PNS)
- Divided into sensory and motor components
- Sensory nervous system (afferent): Conveys information to the CNS from sensory receptors (somatic and visceral).
- Somatic sensory: Sensory information consciously perceived (e.g., special senses, skin).
- Visceral sensory: Sensory information not consciously perceived (e.g., viscera, blood vessels).
- Motor nervous system (efferent): Conveys information from the CNS to effector organs (somatic and autonomic).
- Somatic motor: Voluntary control of skeletal muscles.
- Autonomic motor: Involuntary control of smooth, cardiac muscle, and glands. Further divided into sympathetic and parasympathetic.
Somatic Nervous System
- Processes consciously perceived or controlled.
- Somatic sensory: Detects and transmits info from special senses, skin and proprioceptors to the CNS.
- Somatic motor: Initiates and transmits nerve signals from the CNS to skeletal muscles.
Autonomic Nervous System
- Also called the visceral nervous system
- Processes regulated below conscious level; maintains homeostasis.
- Visceral sensory: Receptors detect stimuli from viscera and blood vessels to CNS.
- Autonomic motor system: Transmits signals from CNS to cardiac and smooth muscles and glands.
Differences between Somatic and Autonomic Systems
| Property | Somatic Nervous System | Autonomic Nervous System |
|---|---|---|
| Target Tissues | Skeletal muscle | Smooth and cardiac muscle, glands |
| Response | Voluntary contraction | Involuntary action |
| Regulation | Voluntary/conscious | Involuntary/unconscious |
| Origins | Motor cortex, medulla, dorsal horns of the cord | Brain stem nuclei; varying regions of the cord |
| Myelination | Yes | No (mostly) |
| Neurotransmitters | Acetylcholine (ACh) | Acetylcholine (ACh), norepinephrine (NE), epinephrine (Epi) |
| Receptor subtype | Nicotinic | Nicotinic, muscarinic, α and β adrenergic |
Autonomic Nerve Pathway
- Consists of two neuron chains.
- Cell body of 1st neuron in CNS.
- Synapses with cell body of 2nd neuron in ganglion.
- Axon of 2nd neuron (postganglionic fiber) innervates effector organ.
Autonomic System Subdivisions
- Sympathetic division: "Fight or flight" response. Mobilized during exertion, excitement, or emergency.
- Increases heart rate and respiration.
- Increases blood flow to skeletal and cardiac muscle.
- Increases sweating.
- Parasympathetic division: "Rest and digest" or "feed and breed" response.
- Promotes maintenance functions, energy conservation
- Decreases heart rate and blood pressure.
- Increases motility and secretion in digestive system.
- Increases elimination of waste products and sexual arousal.
Anatomic Differences between Sympathetic and Parasympathetic Systems
- Origin of preganglionic neuron cell bodies: Para: brainstem and S2-S4; Symp: T1-L2
- Ganglion location: Para: near target organ; Symp: near spinal cord
- Length of preganglionic fibers: Para: long; Symp: short.
- Length of postganglionic fibers: Para: short; Symp: long.
- Preganglionic axon branches: Para: few; Symp: many.
- Response: Para: local; Symp: mass activation.
Parasympathetic Anatomy
- Specific cranial nerves (CN III, VII, IX, X) innervate various organs.
- Vagus nerve (CN X) is the major parasympathetic nerve. -Extensive branching to the thoracic and abdominal viscera
Sympathetic Anatomy
-
Cell bodies in lateral horn of spinal cord (T1-L2).
-
Fibers exit through anterior roots.
-
Fibers enter sympathetic trunk (immediately lateral to spinal cord).
-
Sympathetic trunk contains ganglia.
-
Ganglia are interconnected by bundles of axons.
-
Cervical ganglia: Innervate head & neck.
-
Rami communicantes: Connect the spinal nerves to the sympathetic trunks (White & Gray).
- White rami: Carry preganglionic axons
- Gray rami: Carry postganglionic axons
-
Innervation through sympathetic trunk, or splanchnic nerves
-
These nerve pathways innervate many structures.
Sympathetic Splanchnic Nerves
- Preganglionic fibers arise from T5-9 (greater thoracic) and T10-T11 (lesser thoracic and least thoracic) and L1-L2/Lumbar
- Ganglia are either in the trunk or prevertebral.
Prevertebral (Collateral) Ganglia
- Located anterior to vertebral column on anterolateral wall of the aorta, only in abdominopelvic cavity.
- Celiac ganglion: Innervates stomach, spleen, liver, gallbladder, and proximal duodenum.
- Superior and inferior mesenteric ganglia: Innervate parts of the small and large intestine, parts of the pancreas, kidneys and proximal ureters.
Sympathetic Pathways
- Spinal nerve pathway: Synapses in the sympathetic trunk ganglion; postganglionic fiber travels out through the gray ramus to its target organ.
- Postganglionic sympathetic nerve pathway: Postganglionic fiber extends directly to its target organ without synapsing.
- Splanchnic nerve pathway: Preganglionic fibers pass through sympathetic trunk ganglion. Extend to collateral (prevertebral) ganglia and synapse; postganglionic fibers innervate abdominal/pelvic organs.
- Adrenal medulla pathway: Preganglionic fibers directly innervate adrenal medulla. No postganglionic fibers; secrete norepinephrine (NE) and epinephrine (Epi) into bloodstream. These hormones reinforce sympathetic effects.
Spinal Nerve Pathway
- Preganglionic fiber synapses in sympathetic trunk ganglion.
- Postganglionic fiber travels via gray ramus to join spinal nerve.
- Innervates target organs (skin, sweat glands, blood vessels, arrector pili muscles).
Cholinergic Receptors
- Nicotinic Receptors: Found on postganglionic cell bodies, adrenal medulla, and skeletal muscles; activated by ACh, always excitatory.
- Muscarinic Receptors: Located on target cells innervated by parasympathetic postganglionic fibers; activated by ACh; may be excitatory or inhibitory, depending on subtype.
Adrenergic Receptors
- Two major types: Alpha (α) and Beta (β).
- Bound by norepinephrine (NE) or epinephrine (Epi).
- Excitatory or inhibitory, depending on subtype and location.
Interactions within the ANS
- Tone: Basal level of activity for both systems.
- Antagonistic effects: Sympathetic and parasympathetic systems often innervate the same organ. They typically have opposite effects.
Autonomic Reflexes
- Visceral reflexes: Similar to somatic reflexes, but have two neurons in the motor component
- Cardiovascular reflex: Reduces blood pressure.
- Gastrointestinal reflex: Prepares body for digestion/elimination.
- Micturition reflex: Leads to urinary elimination.
Control of the ANS
- Top level of control is the hypothalamus
- Hypothalamus receives and relays signals through brainstem and spinal cord.
- Cortex provides input to the hypothalamus to produce a proper ANS response.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Explore the components of the Peripheral Nervous System (PNS) through this quiz. Understand the distinctions between sensory and motor functions, the somatic and autonomic nervous systems, and how they interact with the central nervous system (CNS). This quiz covers key concepts related to the structure and functions of the PNS.
