The Spinal Cord & Divisions of the Nervous System Flashcards
Name the 2 distinct branches of the nervous system.
The Central Nervous System and the Peripheral Nervous System
Which components make up the two branches of the nervous system?
CNS (brain, brain stem and the spinal cord)
PNS (12 cranial nerves, 31 spinal nerves, ganglion
How many pairs of sensory nerves do we have?
43 pairs of sensory nerves
How many spinal and cranial nerves do we have?
31 spinal
12 cranial
How many nerves contribute towards the formation of the following:
- Cervical Nerves
- Thoracic Nerves
- Lumber Nerves
- Sacral Nerves
- Coccygeal
Cervical Nerves
4 cervical /4 Brachial
Thoracic Nerves
12 thoracic
Lumber Nerves
5 Lumber
Sacral Nerves
5 Sacral
Coccygeal
1 coccygeal
Which artery supplies the spinal cord?
The anterior and posterior spinal arteries
Where is the Sacral plexus in relation to the Sacrum?
Anterior
Where is the Lumbar Plexus in relation to the Sacrum?
Posterior
The spinal cord enlarges at what two levels?
The cervical enlargement is located proximally, at the C4-T1 level. The spinal cord also enlarges between L2 and S3.
Can you explain why the spinal nerves enlarge at certain points?
Enlargement occurs at the cervical due to the formation of the brachial and the lumbosacral plexus.
The peripheral nervous system is divided into 2 subdivisions. Name them.
Sympathetic nervous system and the parasympathetic nervous system
Which division of the nervous system is responsible for voluntary conscious control of skeletal muscles?
Somatic
What type of nerves innervate muscles?
Motor nerves/efferent nerves
What neurotransmitter is responsible for the contraction of muscles?
Acetylecholine
Which system controls all of our bodily functions that are out with our conscious control?
Autonomic
Which part of the autonomic nervous system is responsible for the fight or flight response?
Sympathetic nervous system
Which part of the autonomic nervous system is responsible for rest and digest?
Parasympathetic nervous system
Which cranial nerve is responsible for 90 percent of information sent through the PSNS?
Vegus nerve
Which division of the nervous system inhibits the GI function?
Sympathetic
Which division of the nervous system promotes an increase in blood pressure?
Why is blood pressure increased?
Sympathetic
Adrenaline constricts arteries
Which division of the nervous system facilitates the GI tract?
Parasymathetic nervous system
Which division of the nervous system promotes the secretion of saliva?
Parasympathetic
Which nerves leave the jugular foramen?
Vegus nerve, accessory nerve 11, glossopharyngeal
Which cervical nerves exit above the level of the corresponding vertebrae?
C1 to C7
Which cervical nerves exit below the level of the corresponding vertebrae?
C8
Which nerve exits below C7/T1?
C8
Name the 5 terminal branches of the brachial plexus?
The musculocutaneous, median, ulnar, axillary, and radial nerves.
What is the level of the lumber plexus?
T1, L1 to L4
What Is the level of the sacral plexus?
L4 to S4
Which nerve is responsible for meralgia paresthetica? At what level?
Lateral femoral cutaneous nerve, L2/3
Which is the nerve root level of the femoral nerve? What muscles does it innervate?
L2 to L4
Anterior division, sartorius, pectineus, illiacus,
Posterior division. Quadriceps
Which nerve innervates the adductors? At what level?
Obturator nerve, L2 to L4
What is the nerve root level of the sciatic nerve?
L4 to S3 (Five nerves which conjoin as one)
The sciatic nerve is split into the tibial and fibular branches. Name the nerve root levels.
Tibial nerve L4 to S3
Fibular nerve L4 to S2
Which nerve innervates the gluteus maximus? Level?
Inferior gluteal nerve, L5 to S2
Which nerve innervates the TFL?
Superior Gluteal Nerve
What is the nerve root to the pudendal nerve?
S2 to S4
Which sphincters does the pudendal nerve innervate?
Urethral sphincter and the external anal sphincter
What condition is associated with a reduction in sensation to the perineum?
Saddle Anastacia
The spinal cord stems from the brain stem to?
L2
What does the spinal card travel within?
Spinal canal/cavity
Name the three layers of the spinal cord?
Dura Matter, Arachnoid Matter, Pia Matter
Where is CSP found?
The space between the arachnoid matter and the pia matter (Arachnoid space)
Which cells produce CSP?
Ependymal cells
- What is the function of CSP?
Supplies the brain and spinal cord with the nutrients they need
The spinal cord ends?
The spinal cord ends at the conus medullaris
Which fibrous band extends from the cons medullaris?
The filum terminale (FT) is a fibrous band that extends from the conus medullaris.
Which nerve and level innervates the lateral compartment of the leg?
Lateral femoral cutaneous nerve L2/3
Which muscles 3 muscles are innervated by the S1 nerve root?
Gastrocnemius, Soleus, Peroneal
Where does the filum terminale end?
periosteum of the coccyx
The elongation of the spinal cord stops at age?
4/5
Why does the cauda equina form?
During the growth process, the elongation of the spinal cord stops around age 4 to 5, however the vertebral column continues to grow stretching the cord and giving the appearance of a horse’s tail.
Damage to which spinal nerve root level results in quadriplegia?
C4
Damage to the T6 nerve root results in which form of paralysis?
Paralysis below the chest.
