Anatomy Week 3 Cervical plexuses Flashcards
Why are spinal nerves mixed nerves
As they contain both sensory and motor nerves
What do anterior roots contain
Motor efferent fibers
What does posterior roots contain
Sensory afferent fibers
Name the 4 different types of fibers spinal nerves contain
- Somatomotor - efferent fibers
- Visceromotor - efferent
- somatosensory - afferent
- Viscerosensory - afferent
What is somatomotor (efferent ) fibers used for
For skeletal muscles
What is visceromotor efferent fibers used for
- smooth muscles and glands
What is somatosensory afferent fibres used for
Exteroceptive and proprioceptive sensations
What is Viscerosensory afferent fibres used for
Internal organ sensations
What are visceral efferent fibers+ what is it divided into -
Are autonomic fibers that supply the internal organs they are divided into sympathetic and parasympathetic
Where do the sympathetic fibers from visceral efferent fibers originate from
-spinal nerves
Where do the parasympathetic fibers from the visceral efferent fibers originate from
- from spinal nerves and cranial nerves
What is Dermatome
An area of skin that is supplied by a single spinal nerve
What is myotome
A group of muscles supplied by a single spinal nerve
Named the branches (4) of a spinal nerve
- Anterior ramus
- Posterior ramus
- Rami communicantes
- Meningeal branches
What does the anterior ramus supply
- Anterolateral trunk wall and limbs
What does the Posterior ramus supply
- Supplies the skin and muscles of the back and posterior scalp
What does the Rami communicantes carry
-It carries autonomic signals
Meningeal branches re enter the vertberal canal to innervate what
-Ligaments
-Dura
-Vessels
-Joints
-Vertberae
What can the rami communicantes be divided into
Grey rami communicantes
white rami communicantes
Where does the grey rami communicantes exist
- At all spinal levels
What is the function of the grey rami communicantes
-It carries postganglionic sympathetic fibers from the sympathetic chain to target organs
What is the function of the white rami communicantes
- They carry preganglionic fibers from the spinal cord to the sympathetic chain
Name the 4 different plexuses inwhich the spinal nerves reorganises into
- Cervical plexus
-Brachial plexus
-Lumbar plexus
-Sacral plexus
Does the thoracic spinal nerves from plexuses
No