Podcast Beta
Questions and Answers
Which cranial nerve is associated with both the ciliary muscles and the iris of the eye?
What is the primary function of the fibers that arise from the dorsal vagus nucleus?
What is the primary function of autonomic ganglia?
Which salivary gland is innervated by the Otic ganglion?
Signup and view all the answers
Which of the following ganglia are classified under sympathetic ganglia?
Signup and view all the answers
What effect does large dose nicotine have on autonomic ganglia?
Signup and view all the answers
How many cervical ganglia are part of the sympathetic chain?
Signup and view all the answers
Which of the following structures primarily supplies the lower colon and rectum in the sympathetic nervous system?
Signup and view all the answers
What is the significance of the close distance between parasympathetic ganglia and effector organs?
Signup and view all the answers
From which spinal segments do the pelvic splanchnic nerves arise?
Signup and view all the answers
Where are the majority of parasympathetic ganglia located?
Signup and view all the answers
What type of effect does sympathetic stimulation typically result in?
Signup and view all the answers
Which of the following statements is true about prevertebral ganglia?
Signup and view all the answers
Which gland is primarily affected by the Pterygopalatine ganglion?
Signup and view all the answers
From which thoracic segments do preganglionic fibers supplying the celiac ganglion originate?
Signup and view all the answers
Which ganglion is NOT part of the sympathetic ganglia?
Signup and view all the answers
Study Notes
Autonomic Ganglia
- A collection of neuronal cell bodies and their dendrites outside the central nervous system (CNS).
- Site of junction between preganglionic and postganglionic neurons.
Autonomic Ganglia Function
- Relay station for nerve impulses.
- Distributing center: one preganglionic fiber can synapse with multiple postganglionic fibers (divergence).
Types of Autonomic Ganglia
- Sympathetic ganglia
- Parasympathetic ganglia
Sympathetic Ganglia
-
Paravertebral ganglia (sympathetic chain or lateral ganglia)
- 21 or 23 pairs of ganglia: 3 cervical, 12 thoracic, 4 lumbar, 4 sacral, and 1 unpaired ganglion (ganglion impar) located in front of the coccyx.
- Stellate ganglion: A fusion of the inferior cervical and first thoracic ganglia in some individuals.
-
Prevertebral (Collateral ganglia)
- Overlie the origin of the celiac, superior mesenteric, and inferior mesenteric arteries.
-
Celiac ganglion:
- Receives preganglionic fibers from the T5 to T12 segments of the spinal cord.
- Provides sympathetic innervation to the stomach, liver, pancreas, gallbladder, small intestine, spleen, and kidneys.
-
Superior mesenteric ganglion:
- Receives preganglionic fibers from the T10 to T12 segments of the spinal cord.
- Provides sympathetic innervation to the small and large intestines.
-
Inferior mesenteric ganglion:
- Receives preganglionic fibers from the L1 to L3 segments of the spinal cord.
- Provides sympathetic innervation to the lower colon, rectum, urinary bladder, and reproductive organs.
Parasympathetic Ganglia
- Terminal ganglia: Located near or within the wall of effector organs (most common).
-
Exceptions: 4 pairs of ganglia in the head and neck:
-
Ciliary ganglion:
- Associated with the oculomotor nerve (cranial nerve III).
- Innervates the ciliary muscles and iris of the eye.
-
Pterygopalatine ganglion:
- Associated with the facial nerve (cranial nerve VII).
- Innervates the lacrimal gland and mucosal glands of the nose and palate.
-
Submandibular ganglion:
- Associated with the facial nerve (cranial nerve VII).
- Innervates the submandibular and sublingual salivary glands.
-
Otic ganglion:
- Associated with the glossopharyngeal nerve (cranial nerve IX).
- Innervates the parotid salivary gland.
-
Ciliary ganglion:
Vagus Nerve (X)
- Sensory, motor, and autonomic (parasympathetic) functions.
- Autonomic part:
- Arises from the dorsal vagus nucleus in the medulla.
- Fibers relay in terminal ganglia at effector organs.
- Despite being a cranial nerve, it only provides sensory and motor supply to the head and neck, and has no parasympathetic innervation to them.
- All parasympathetic supply from the vagus nerve is to the thorax and abdomen.
Pelvic Splanchnic Nerves and Pelvic Nerve Plexuses
- Preganglionic parasympathetic fibers from the S2 to S4 segments of the spinal cord.
- Contribute to form the pelvic nerves.
- Relay in terminal ganglia for parasympathetic innervation to the transverse colon, rectum, urinary bladder, and reproductive organs.
- Contribute to the hypogastric plexus.
General Effects of Sympathetic and Parasympathetic Stimulation
-
Sympathetic
- Generalized effects due to long distance between ganglia and effectors, along with divergence.
-
Parasympathetic
- Localized effects due to short distance between ganglia and effectors and less divergence.
Nicotine Test
- Small dose of nicotine: Stimulates autonomic ganglia.
- Large dose of nicotine: Blocks autonomic ganglia.
-
Example:
- Blocking a ganglion with a large dose of nicotine and then stimulating the preganglionic fiber, the postganglionic response is still present. This indicates the preganglionic fibers do not relay in that ganglion.
- Conversely, if the postganglionic response disappears, it suggests that the preganglionic fibers relay in that ganglion.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on autonomic ganglia, including their structure, function, and types such as sympathetic and parasympathetic ganglia. This quiz covers essential concepts related to the junctions and functions of these neural structures in the autonomic nervous system.
