Nervous System Flashcards
What is the Nervous system made up of?
CNS
PNS
What is the CNS made up of?
Brain and spinal cord
What is the PNS made up of?
Everything else
(Cranial nerves, spinal nerves, ganglia, enteric plexuses, receptors)
What are 3 functions of the nervous system?
1.) sensory ( afferent) -conduct impulses away from sensory structures towards CNS
2.) integrative-occurs in brain and spinal cord
3.) motor ( efferent)- carries impulses away from CNS toward PNS. initiates muscle contraction or glad secretion.
What are 2 types of Nervous Tissue?
1.) Neuroglia ( support cells)
2.) Neurons ( nerve cells)
List 4 subcategories of Neuroglia and a brief description of their function
1.) Astrocytes: support and protect neurons. Help form blood brain barrier
2.) microglia: the immune system of CNS. Has phagocytes
3.) Oligodendrocytes + Schwann: lay down myelin around axon to speed up impulses
4.) Ependymal: produce cerebral spinal fluid.
What are the gaps in the myelin called? what are they for?
Nodes of Ranvier.
To make impulses travel faster ( jump)
How are Neurons categorized?
1.) structure
2.) function
List the functional classifications of neurons
1.) afferent: transmit toward the CNS
2.) interneuron: integrate within CNS
3.) Efferent: away from CNS
What are the structural classifications for neuron types?
1.) multipolar: somatic and autonomic neurons, mainly in CNS ( many dendrite, one axon)
2.) Bipolar: one dendrite one axon, found in retina, inner ear and olfactory part of brain
3.) unipolar: one process emerging from cell body. Always somatic sensory neurons
Sensory receptors are classified by what two categories?
1.) location
2.) stimulus
What are 3 classifications of sensory receptors based on location?
1.) exteroreceptors-determine stimuli
2.) interoreceptors-detect internal stimuli
3.) propioceptors- “ones own”
What are the 5 types of exteroreceptors?
1.) touch receptors: corpuscles, meissner, hair root plexuses
2.) pressure receptors: pacinian ( or laminated) corpuscles
3.) vibration receptors: meissner + pacinian
4.) Thermal receptors
5.) nociceptors: pain receptors
What are the 2 types of interoreceptors?
1.) baroreceptors: detect stretch
2.) chemoreceptors: detect chemical changes
What are the 3 types of proprioceptors?
Locate in mm tendons, joints and inner ear. Detect body position and movement
1.) muscle spindle:detect stretch of a muscle
2.) Golgi tendon organ: give info to CNS regarding force of contraction or tension
3.) joint kinaesthetic receptors: acceleration/deceleration of joint/pain
What are the 5 types of sensory receptors classified by stimulus?
1.) mechanoreceptors ( touch, stretch, pressure, vibration, hearing,, blood pressure etc.)
2.) thermoreceptors: temperature
3.) nociceptors: physical or chemical damage to tissue
4.) photoreceptors: light
5.) chemoreceptors: detects chemicals in mouth nose or body fluid ( ie blood ph etc)
What makes up white matter?
Myelinated axons
What makes up grey matter?
Nerve cell bodies
Dendrites
Axon terminals
Unmyelenated axons
How is the white/grey matter organized in the brain and spinal cord?
Brain: outer grey matter, inner white matter
SC: Inner grey matter, inner white matter
What is the function of the spinal cord? what are the 2 types of reflexes of the spinal cord?
Integrates and relays information.
1.) Somatic reflex
2.) Autonomic reflex
Define reflex
Fast automatic preprogrammed response to a stimuli
What is the difference between a somatic and autonomic reflex?
1.) somatic: external stimulus, effectors are skeletal muscle
2.) autonomic reflex: internal stimulus, effectors are smooth muscle and glands
What are meninges? List the 3 layers.
3 protective connective tissue coverings of the brain and spinal cord
1.) dura matter: tough superficial layer
2.) arachnoid: middle layer ( cerebrospinal fluid is found beneath)
3.) Pia matter: delicate layer with capillaries adhered to brains surface
What are the 4 parts of the brain?
1.) cerebrum
2.) diencephalon
3.) cerebellum
4.) brain stem
What does the diecephalon contain?
Contains the thalamus ( which is the relay station)
Hypothalamus
Pituitary gland
What are the 3 parts of the brain stem?
1.) brain stem: connects spinal cord to brain
2.) Pons
3.) medulla oblongata
What is the cerebellum in control of?
Unconcious control of hand eye coordination
What disorder might you see with the degeneration of the hippocampus?
Alzheimer’s
What disorder might you see with the degeneration of the basal ganglia?
Parkinson’s
What is the lambic system in charge of? Where is it located?
The emotional brain.
Found in the cerebrum
Where would you find the lobes of the brain ( frontal, parietal, temporal, occipital)?
What is each lobe responsible for?
Cerebral cortex of the cerebrum
1.) frontal: thinking and reasoning
2.) parietal: language
3.) temporal: language, hearing, smell
4.) occipital: visual stimuli
Where is the amygdala located?
The lambic system within the cerebrum
What 4 important things are located within the cerebrum?
1.) cerebral cortex ( frontal, parietal, temporal and occipital lobes)
2.) inner white matter ( includes corpus callosum)
3.) basal ganglia ( large automatic mm mvmt)
4.) lambic system ( emotional brain. Contains hippocampus and amygdala)
How many pairs of nerves do you have in the spinal cord? Can you break them down?
31 pairs.
8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal
What are the 3 sections of the peripheral nervous system?
1.) somatic
2.) autonomic
3.) enteric
What type of neurons are in the somatic nervous system and what do they do? Are these voluntary or involuntary?
1.) somatic sensory neurons
2.) somatic motor neurons
1.) Sensory neurons convey info from sensory organs to CNS
2.) motor neurons convey into to skeletal muscles only
VOLUNTARY
What are the neurons of the autonomic nervous system and what do they do? Are these voluntary or involuntary?
1.) visceral sensory neurons
2.) visceral motor neurons
1.) sensory neurons conduct info from receptors of internal organs to CNS
2.) motor neurons conduct impulses from CNS to smooth muscle, cardiac muscle and glands.
INVOLUNTARY
The autonomic nervous system can be further broken down into what two categories?
Sympathetic and parasympathetic NS.
Sympathetic: fight/flight
Parasympathetic: rest/digest
What is the enteric nervous system and what does it do?
The brain of the gut.
Monitors stretching of the gut lining and stimulates smooth muscle contractions and innervated glands.
