Nervous System Flashcards
Basic functions of nervous system
- Sensation
- Integration
- Reaction
Monitors changes/events occurring in and outside the body
Sensation
The parallel processing and interpretation of sensory information to determine the appropriate response
Integration
The motor ouput of the nervous system
Reaction
Changes are known as
Stimuli
cells that monitor changes
receptors
The activation of muscles or glands
Motor output
Similarities of Nervous and Endocrine system
Both monitor stimuli and react as to maintain homeostasis
Differences between NS and ES
- NS is rapid, and fast acting
- ES is slower and action are longer lasting
are blood-borne chemical signals
Hormones
2 Big initial divisions of NS
- Peripheral NS
- Central NS
The nervous system outside of the brain and spinal cord
Peripheral NS
- The brain + the spinal cord
- The center of integration and control
Central NS
3 kinds of neurons that connect CNS to the body
– sensory
– motor
– interneurons
CNS to muscles and organs
Motor neurons
sensory receptors to CNS
Sensory neurons
Connections Within CNS
Interneurons
Divisions of Peripheral NS
Sensory division
Motor division
it is the Afferent division
Sensory division
It is the Efferent division
Motor division
–Conducts impulses from receptors to the CNS
–Informs the CNS of the state of the body (interior and exterior)
Afferent division
–Conducts impulses from CNS to effectors (muscles/glands)
–Motor nerve fibers
Efferent division
Divisions of Sensory division
Somatic sensory
Visceral Sensory
Divisions of Motor Division
Somatic (Skeletal) NS
Autonomic NS
- VOLUNTARY (generally)
- Somatic nerve fibers that conduct impulses from the CNS to skeletal muscles
Somatic (or skeletal) NS
- INVOLUNTARY (generally)
- Conducts impulses from the CNS to smooth muscle, cardiac muscle, and glands.
Autonomic NS
Divisions of Autonomic NS
Sympathetic NS
Parasympathetic NS
The Autonomic NS division for “Fight or Flight”
Sympathetic NS
The autonomic division for “rest and digest”
Parasympathetic NS
Involuntary movment that controlled by Automic NS
– heartbeat
– blood pressure
– respiration
– perspiration
– Digestion
2 cell types of Nervous tissue
- Neurons
- Neuroglia
Functional, signal conducting cells
Neurons
Supporting cells
Neuroglia
Receive stimuli and
transmit action potentials
Neurons or nerve cells
organization of Neurons
Cell body (Soma)
Dendrites: Input
Axons: Output
4 types of Neuroglia found in CNS
- Astrocytes
- Oligodendrocytes
- Ependymal cells
- Microglia
- Star-shaped, abundant, and versatile
- Guide the migration of developing neurons
- Involved in the formation of the blood brain barrier
- Function in nutrient transfer
Astrocytes
Produce the myelin sheath which provides the electrical insulation for certain neurons in the CNS
Oligodendrocytes
- Line brain ventricles and spinal cord central canal
- Help form choroid plexuses that secrete CSF
Ependymal cells
Specialized macrophages
Microglia
2 types of Glial in PNS
- Satellite cells
- Schwann cells
- Surround clusters of neuronal cell bodies in the PNS
- Unknown function
Satellite cells
- Form myelin sheaths around the larger nerve fibers in the PNS.
- Vital to neuronal regeneration
Schwann cells
When a cell is exposed to chemical signal for a prolonged period, it tends to lose ability to respond with its original intensity
Drug addiction
What does drug addiction do to receptor proteins?
They are exposed to high levels for neurotransmitter molecules for high periods of time
How does nerve cell response to prolonged period exposure of receptor proteins from neurotransmitters?
They respond by inserting fewer receptor proteins into the membrane
Neuromodulator that causes large amounts of neurotransmitters to remain in synapses for long periods of time
Cocaine
- is made of the brain and the spinal cord
- controls everything in the body.
The Central Nervous System
WHat does Spinal cord and brain consists of?
a. White matter
b. Grey matter
bundles of axons each coated with a sheath of myelin
White matter
masses of the cell bodies and dendrites each covered with synapses.
Gray matter
Location of each matter in Spinal cord
- White matter at the surface
- Gray matter inside
- conducts sensory information from the peripheral nervous system to the brain
- Conducts motor information
Spinal cord
actions that result from a nerve impulse passing over a reflex arc
- predictable response to a stimulus
Reflex actions
Examples of reflexes
- Knee jerk reflex
- Ankle jerk reflex- Archilles reflex
- Babinski reflex
- Plantar reflex
- Corneal reflex
- Abdominal reflex
extension of lower leg in response to tapping the patellar tendon with a reflex hammer
Knee jerk reflex
Knee jerk reflex are lost in some patients with…
Poliomyelitis and other diseases
extension of foot in response to tapping the Achilles tendon
Ankle jerk reflex-Achilles reflex