Nervous System Flashcards
constitutes the CNS
brain, spinal cord
make up the peripheral NS
nerves, sensory organs
transmit and process sensory information and coordinate bodily functions
CNS, PNS
function as the control center
brain and spinal cord (CNS)
what carries incoming and outgoing signals
Nerve pathways of the PNS
receive data and feedback from the sensory organs and from nerves throughout the body, process the information, and send commands back out
CNS
receives information from the body’s environment and generates instructions, thereby controlling all the activities of the human body
CNS
conveys this two-way information flow into and out of the CNS
PNS
The central parts of the CNS are occupied by spaces called
ventricles with CSF
Where is the brain and what forms it?
Neurocranium
- cerebrum
- cerebellum
- brainstem
placed within the vertebral column
spinal cord
transmits signals to and from the brain and commands reflexes
spinal cord
elongated cylinder of neuron cell bodies, bundles of axons protected by CT
spinal cord
signals speed in and out of the spinal cord via ______ that branch out to supply the limbs, torso, and pelvis
spinal nerves
Incoming signals demanding a simple,
immediate response which spinal cord can shootout a reflex command without bothering the brain
Reflex arc
made of neuron cell bodies found in the cerebral cortex and the central portion of the spinal cord
gray matter
made of axons, which combine and build neural pathways
white matter
where the instructions generate
gray matter
the path through which the instructions travel toward the organs
white matter
conducts information from the CNS to the target tissues, and from the target tissues to the CNS
PNS
Nerves that carry information from peripheral sense organs to CNS
ascending, afferent, or sensory nerve fibers
Fibers that carry information from the CNS to the periphery (muscles and glands)
descending, efferent motor, or secretory nerve fibers
cluster of neural tissue outside of the CNS, made of neuronal cell bodies
ganglion
ganglia can be both?
sensory and autonomic
They are associated with spinal nerves and some cranial nerves. Name the nerves.
Sensory ganglia
Cranial Nerves (V, VII, IX, X)
voluntary control over our movements and responses
somatic nervous system
Major somatic peripheral nerves
- median nerve
- sciatic nerve
- femoral nerve
controls all the internal organs unconsciously, through the associated smooth muscle and glands
autonomic nervous system
producing the “flight or fight“ state as it is part of the ANS which is mostly active during stress
Sympathetic NS
Parasympathetic dominates during rest and is more active in these activities (2)
- rest and digest
- feed and breed
Spinal nerves are divided into?
8 cervical nerves
12 thoracic nerves
5 lumbar nerves
5 sacral nerves
1 coccygeal nerve
branches of one spinal nerve may join with other nerves to form meshes where information is shared
plexuses
send signals along secondary nerve branches to areas of complex function or movement
plexuses
Cervical plexuses (C1-C4) innervates? (7)
- back of the head
- pericardium
- diaphragm via great auricular
- transverse cervical nerve
- lesser occipital
- supraclavicular
- phrenic nerves