Chapter 21/ couple 22 Flashcards
Sensory organs (4)
Eyes
Ears
Specialized sensory organs
Free nerve endings
Amount of Peripheral cranial nerves
12
Amount of peripheral spinal nerves
31
Function of spinal nerves in PNS
Conduct impulses between the spinal cord and the other parts of the body not supplied by cranial nerves (e.g. all parts of the body except the head)
Contain sensory and motor fibres
Conduct impulses necessary for sensations and voluntary movements
Spinal nerves exit spinal cord and branch to form______
Many peripheral nerves of the bodys trunk and limbs
The nerve exits _____ to its numbered vertebra
Superior
Spinal nerves are identified by ___ nad ____
Letter and number
Thoracic nerves exit horizontally through
Intervertebral formina
_____, ____ and _______ nerve roots descend from point of origin to the lower end of the spina cord before reaching the ___________ of the respective vertebrae, through which the nerves emerge
Lumbar, sacral, coccygeal
Invertebral foramina
Cauda equina describes what
The appearanve of the lower end of the spinal cord and its spinal nerves as a horses tail
Each spinal nerve attaches to the spinal cord via what two roots
Dorsal and ventral
Corsal root contains
Dorsal root ganglia
Ramus of spinal nerve
One of several large branches formed after each spinal nerve emerges from the spinal cavity
Dorsal ramus and ventral ramus ( ventral is more complex)
Spinal nerve plexus
Complex networks formed by the ventral rami of most spinal nerves (except T2 to T12)
Subdivide and join to form a single peripheral nerve that contains all the fibers that innervate a particular region of the body
4 major pairs of plexuses
Cervical
Brachial
Lumbar
Sacral and coccygeal
Where and whast do servical plexus do
Located deep within neck
Innervated lower muscles and skin within the neck, upper shoulders and part of head
Brachial plexus location and function
Located deep within shoulder
Innervated lower part of shoulder and entire arm
Lumbar plexus
Located in lower back in psoas muscle
Supplies thigh and leg
Sacral and coccygeal plexuses
Supplies most of the skin of the leg as well as leg and foot
Sciatica
What is dermatome
A specific area of skin surface supplied by sensory fibres of a single spinal nerve
Myotome
A skeletal muscle or muscles supplied by motor fibres of a given spinal nerve
There are ____ cranial nerves that attach to ______
12 pairs
Connect to the brain (mostly on the brainstem)
Function of cranial nerves
Conduct impulses between the brain and structures in the head and structures in the head and neck and in the thoracic and abdominal cavities
Olfactory
Sense of smell (1)
Optic
Vision (2)
Oculomotor
Eye (3)
Trochlear
Eye muscles/ moves eyes (4)
Trigeminal
sensation of teeth face, scalp and chewing muscles (5)
Abducens
Eye muscles/ moves eye (6)
Facial
Face, salivary, taste (7)
Vestibulocochlear (auditory)
Hearing and sense of balance/ equilibrium
Glossopharyngeal
Taste, swallowing, saliva, throat sensations (9)
Vagus
Numerous functions, ex. Heart rate, breathing, digestion
Accessory
Neck/ shoulder muscles (11)
Hypoglossal
Moves tongue (12)
Reflex is
An action that results from a nerve impulse passing over a reflex arc
Crania, reflex
Center of reflex arc is in the brain
Spinal reflex
Center of reflex arc is in the spinal cord
Somatic reflex clinical important
Reflex testing to see everything is all working
Knee jerk (patellar) reflex
ANS
Contains afferent/sensory and efferent/motor divisions
Carries nerve impulses to and from autonomic receptors (cardiac & smooth muscle; glands; adipose and other tissues)
Major function is to regulate heartbeat, smooth muscle contraction, glandular secretions, and metabolic functions to maintain homeostatic balance and react to threats to that balance
Each ANS pathway is made up of
autonomic nerves, ganglia, and plexuses, which are made of efferent autonomic neurons
All ans neuron functions are in _____ and are called
Reflex arcs and are called autonomic reflexes or visceral reflexes
Efferent autonomic regulation in the ans depnds on
Feedback from sensory receptors
Efferent neurons conduct _____
Info/impulses from CNS to autonomic effectors
Two types of efferent neurons
Preganglionic and postganglionic
Preganglionic neurons conduct -_______
Impulses from CNS to an autonomic ganglia where it synapses with postganglionic neurons
Postganglionic neurons will conduct impulses to ____
Visceral effectors
Sympathetic postganglionic neurons have dendrites and cell bodies
sympathetic ganglia,
most of which are located in the front and on each side of the spinal column
The sympathetic ganglia are strung along the nerve fibres like beads called
Sympathetic chain ganglia
Each chain runs from _____ to______
C2 to coccyx
There are usually ______ chains on each side of the vertebral column
22
Sympathetic NS is also called
Thoracolumbar system
________________ neurons have dendrite and cell bodies in the lateral gray horns of the thoracic and upper lumbar segments of the spinal cord
Sympathetic preganglion
Once inside the sympathetic chain ganglion, preganglionic neurons may:
- Synapse with a sympathetic postganglionic neuron
- Send ascending or descending branches through the sympathetic trunk to synapse with postganglionic neurons in other chain ganglia
- Pass through one or more chain ganglia without synapsing
As there are many postganglionic neurons involved, sympathetic responses are usually ________, involving many ________
Widespread
Visceral effectors/ organs
