Ch. 2.2 The Nervous System Consists of Central and Peripheral Divisions Flashcards
What is the somatic nervous system?
Nerves that interconnect the brain and the major muscles and sensory systems of the body.
What is the autonomic nervous system?
Nerves that primarily control the viscera (internal organs)
Label the following systems.
A. Central nervous system (CNS)
B. Peripheral nervous system
What are A, B, and C?
A. brain
B. spinal cord
C. cauda equina
What is the gross neuroanatomy?
Tissue of the nervous system made of neuronal cell bodies, dendrites, axons, and glial cells (the stuff you see with the naked eye).
What does the peripheral nervous system do?
Connects all body organs and systems to the central nervous system.
What are the 2 divisions of the peripheral nervous system?
- The somatic nervous system
- The autonomic nervous system
What does soma mean?
Body
What nerves make up the somatic nervous system?
- Cranial nerves
- Spinal nerves
How many pairs of cranial nerves does each person have?
12 - one left-sided and one right-sided nerve in each pair
What do the cranial nerves serve?
The sensory and motor systems of the head and neck
What do you know about cranial nerves?
A. 12 pairs (left and right in each pair)
B. serve the sensory and motor systems of the head and neck
C. enter and leave the brain without joining the spinal cord
D. each cranial nerve has a roman numeral number and a name.
What do the colors represent?
Pink?
Blue?
Cranial nerves
Pink - Motor nerves
Blue - Sensory nerves
How many can you remember?
How many pairs of spinal nerves are there?
31 pairs (emerging at regularly spaced intervals through openings in the backbone)
What do you know about spinal nerves?
A. 31 pairs (one left-sided and one right-sided nerve in each pair)
B. emerging at regularly spaced intervals through openings in the backbone
C. Each spinal nerve is formed by the fusion of 2 distinct branches (dorsal (S) & ventral (M) roots) attached to the spinal cord
What are the 2 branches of a spinal nerve and how are they formed
dorsal root & ventral root
What does dorsal mean?
back
What does ventral mean?
Front
What does the dorsal root consist of?
Sensory projections from the body to the spinal cord (study hint: dorsal has an S and sensory starts with an S)
What does the ventral root consist of?
Motor projections from the spinal cord to the muscles
What are the segment of the spinal cord called?
A. Cervical
B. Thoracic (trunk)
C. Lumbar (lower back)
D. Sacral (pelvic)
E. Coccyx
This is a vertebra. Label the white and gray matter.
A. Gray matter
B. White matter
What is gray matter?
The interneurons and the motor neurons that send axons to the muscles.
What is the white matter?
Myelinated axons that run up and down the spinal column.
What are meninges?
The 3 membrane layers that enclose the spinal cord and brain.
A. Pia mater
B. Arachnoid
C. Dura mater
How are the spinal nerves named?
The first letter of the spinal segment with the number of that segment.
ex: a nerve connected to the 7th cervical segment is called C7
How would you name a nerve connected to 4th lumbar segment?
L4
What is the autonomic nervous system?
The brains main system for controlling the organs of the body.
Supporting the functions of the autonomic nervous system are groups (aggregates) of neurons called?
Autonomic ganglia
Where are autonomic ganglia found?
Various places in the body outside the CNS
Label the following:
A. Preganglionic neuron
B. Postganglionic neuron
Label the following:
A. CNS (central nervous system
B. Autonomic nervous system
C. Sympathetic
D. Parasympathetic
E. Peripheral nervous system
F. Somatic nervous system
G. Sensory nervous system
H. Motor nervous
What are the 3 major divisions of the autonomic nervous system?
- Sympathetic nervous system
- Parasympathetic nervous system
- Enteric nervous system
What is the purpose of the sympathetic nervous system?
It prepares the body for action - increase blood pressure. dilate pupils, heart rate quickens etc. (fight or flight response)
Where are the preganglionic cells of the sympathetic nervous system found?
The middle part of the spinal cord - thoracic and lumbar regions
Explain the basic movement of the sympathetic nervous system.
The preganglionic cells (found in the thoracic and lumbar regions) send their axons innervating the sympathetic ganglia. Postganglionic axons exiting the sympathetic ganglia spread widely through the body, innervating all of the major organ systems.
What are the sympathetic ganglia?
2 chains of ganglia that run along each side of the spinal column (part of the sympathetic nervous system)
What is the parasympathetic nervous system?
Helps the body to relax. recuperate and prepare for future action. (rest-and-digest response)
Where do parasympathetic nerves originate?
In the brainstem and sacral spinal cord.
Are parasympathetic ganglia collected in chains alongside the spinal cord?
No