Introduction to Neural Physiology Flashcards
Who were the two scientists listed in the lecture notes who had theories about the nervous system?
Camillo Golgi and Ramon y Cajal
What theory did Camillo Golgi come up with?
The Reticular theory
What theory did Ramon y Cajal come up with?
The Cell (neuronal) theory
What is the reticular theory?
That everything in the nervous system is a single continuous network
What is the cell (neuronal theory)?
That all nerve cells are individual
What did Cajal receive the nobel prize for?
Theory brains are made of cells
specialised for information processing
Cajal stated neurones are separate cells connected at
synaptic junctions
What did Cajal conclude about neurons and direction?
They are directional.
They are polarised.
Information passes in one direction, from input region (dendrites) to output (axon terminals)
How many main parts can the nervous system be divided into?
5
What are the five main parts of the nervous system?
The central nervous system - brain and spinal cord
The peripheral nervous system - somatic, autonomic and enteric
What is the input for a neurone?
dendrite
what is the output for a neurone?
axon
what is the direction of the electrical impulse?
from the cell body to the end bouton
What are the three functions of all neurons?
receive and integrate receiving signals
conduct the signal along the neuron
transmit the signal to other cells
Neurons differ in their ability to receive incoming signals because there are
different receptors, e.g. light
Neurones differ in their mechanism of
signal conduction
neurons differ in synaptic transmission
some are chemical, some are electrical
what are the three functional classes of neuron?
sensory neurons, interneurons and motor neurons
what are afferent neurons and what do they do?
sensory - conduct action potentials towards the cns
what are efferent neurons and what do they do?
motor - conduct action potentials from to cns to the organs
what are interneurons?
conduct action potentials between neurons in the cns
there are many structural classes of
neurons
List the structural classes of neurons
multipolar
bipolar
unipolar
multipolar neurons have
many dendrites and one axon
bipolar neurons have
one dendrite (may be branched) and one axon
unipolar neurons have
a single process extending from the cell body - may split to form afferent and efferent branches
What type of cell accounts for 90% of all the cells in the nervous system?
Glial cells
Glial cells do not generate or conduct
action potentials
glial cells do not form synapses with
neurons
glial cells take up and release
neurotransmitters
what is the main function of glial cells?
to support the functioning of neurons structurally and metabolically
glial cells surround neurons and
hold them in place
glial cells supply neurons with
oxygen and nutrients
glial cells insulate one
neuron from another
glial cells destroy pathogens and remove
dead neurons
what are the five main types of glial cells?
schwann cell oligodendrocytes astrocyte microglia ependymal cells
where are the schwann cells found?
in the pns
where are schwann cells found?
on sensory and motor neurones
what is the function of schwann cells
aid in conduction
regeneration and regrowth
where are oligodendrocytes found?
In the cns
what is the function of oligodendrocytes?
surround and support multiple neurones, provide insulation
What type of glial cell is the most abundant?
astrocytes
how do astrocytes repair the brain and spinal cord?
by phagocytosis - produce scar tissue
what is the function of astrocytes?
physical support, nutrient supply, maintain environmental chemical composition - ions/neurotransmitters and remove debris
what is the function of microglia?
macrophages - immune defence
where are ependymal cells derived from?
epithelial cells
why are many of the ependymal cells ciliated?
to enable movement of CSF
where are ependymal cells found?
lined along the fluid filled ventricles of the brain and central canal of the spinal column
which type of glial cell forms the CSF fluid and assists its circulation?
ependymal cells
What are the six major devisions of the mammalian cns?
cerebrum thalamus and hypothalamus midbrain pons and cerebellum medulla spinal cord
function of the corpus callosum
interconnects the two hemispheres
function of the cerebellum?
motor controls and some cognitive functions e.g. attention, language and emotion, e.g. fear
function of the thalamus
major site for processing sensory info
function of hypothalamus
regulation of endocrine system via pituitary
what is the medulla oblongata
the lower half of the brainstem
where are the cranial nerves attached
to the ventral surface of the brain
function of cranial nerves?
motor and sensory functions of head and neck some contribute to parasympathetic division of ANS
list the cranial nerves
olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, spinal accessory, hypoglossal
the vertebrate central nervous system is encased in
bone
the vertebrate central nervous system is surrounded by
meninges
describe the surroundings of the brain , meninges and bone wise
skin, periosteum, cranium, dura matter, arachnoid matter and pia matter
the dorsal side of the spinal cord what input
sensory input
the ventral side of the spinal cord has what output
motor output
where do interneuron and motor neuron cell bodies lie?
in the grey matter of the spinal cord
where do the sensory cell bodies lie?
outside the spinal cord in chains of ganglia