Revision of the PNS Flashcards
What does the CNS consist of?
Spinal cord
Brain
Central controller
What does the PNS consist of?
All other nerve tissue not within the CNS
Spinal nerves - connecting to the spinal cord
Cranial nerves (12) - connects with the brain.
What is the basic functional unit of nervous system?
Neurons
Collection of the nerve bodies in the CNS = ?
Nucleus
Collection of the nerve bodies in the PNS = ?
Ganglion
What are multipolar neurones?
Most common neuron type in the CNS. They possess a single axon with 2 or more dendrites spanning out. Cell body located in the CNS.
What are unipolar neurones?
Axon connected to a double process dendrite.
What are nerves?
Collections of axons surrounded by connective tissue and blood vessels.
Anterior nerve roots always carry _______ capabilities?
Motor
Posterior/dorsal nerve roots always carry _______ capabilities?
Sensory
Each spinal nerve supplies innervation to a unilateral area of the body - results in body wall being “segmented”. True/false?
True
What are dermatomes?
Area of the skin supplied with sensory innervation from a single spinal nerve. Also supplying sensory innervation to deeper structures.
What are myotomes?
The skeletal muscles supplied with motor innervation from a single spinal nerve.
Dermatome landmarks on the trunk?
T4 = nipple area
T10 = umbilicus (bellybutton)
Dermatome for posterior scalp, neck and shoulder.
C2-C4
Dermatome for upper limb
C5-T1
Dermatome for lower limb, gluteal region and perineum
L2-Co1
What is the autonomic nervous system?
System in the body that is involuntary and controls the internal environment.
Sympathetic nerve fibres leave the CNS within the spinal nerves within what spinal cord levels?
T1-L2 - thoracocolumbar outflow
Parasympthatic nerve fibres leave the CNS only within 4 cranial nerves. What are the 4 cranial nerves?
CN 3,7,9 and 10.
