Unit 4 Study Guide Flashcards
Epineurium
- thick layer of dense connective tissue
- encloses the entire nerve
perineurium
- layer of dense irregular connective tissue
- wraps bundles of axons, fascicles
- supports blood vessels
Endoneurium
- delicate layer of areolar connective tissue
- separates and electrically insulates each axon
- has capillaries that supply the axon
dorsal root
- many axons of sensory neurons whose cell bodies are in posterior root ganglion
anterior root
- many axons of motor neurons whose cell bodies are in anterior and lateral horns
posterior ramus
- smaller of the two branches
- innervates deep muscles of the back and skin of back
anterior ramus
- larger of the two branches
- splits into multiple other branches
- at different levels, this ramus innervates anterior and lateral trunk, upper limb, lower limb
- participates in plexuses
Posterior Horns
Axons of sensory neurons and cell bodies of interneurons
Lateral Horns
(T1-L2)
-cell bodes of autonomic motor neurons that innervate cardiac muscle, smooth muscle, glands
Anterior Horns
cell bodies of somatic motor neurons innervating skeletal muscle
Rami Communicantes
- Associated with spinal Nerves. Connect spinal nerves to sympathetic trunk
- contain axons associated with the autonomic nervous system
White Rami Communicantes
- carry myelinated preganglionic sympathetic axons from T1-L2 nerves to turn
- Entrance ramps to trunk
Gray Rami Communicantes
- Carry unmyelinated postganglionic sympathetic axons from trunk to all spinal nerves
- exit ramps from trunk
Sympathetic Trunk Ganglion
-Ganglia interconnected in sympathetic trunk parallel to vertebral column
Somatic Nervous System
- includes process that are perceived or consciously perceived
- Somatic Sensory
- Somatic Motor
- A single lower neuron extends from the CNS to skeletal muscle fibers.
- Cell body lies within brainstem or the spinal cord and axon exits the CNS in a cranial nerve or a spinal nerve and extends to a skeletal muscle
Somatic Sensory
detection of stimuli and transmission of nerve signal from special senses, skin, and proprioreceptors to the CNS
Somatic Motor
initiation and transmission of nerve signals from the CNS to control skeletal muscles
Autonomic Nervous System
- includes processes regulated below the conscious level. -
- Motor System only–Autonomic Motor
- Responds to input from visceral sensory components, such as receptors that detect stimuli associated with blood vessels and internal organs
Lower Motor Neuron found in the Somatic Nervous System
- A single lower motor neuron extends from the CNS to skeletal muscle fibers.
- Cell body lies within brainstem or the spinal cord and axon exits the CNS in a cranial nerve or a spinal nerve and extends to a skeletal muscle
- Voluntary Movements involve cerebrum
- Reflexive movements involve brain and spinal cord