Flashcards in (1) Overview 1/2 Deck (74)
nervous system is divided into.... (2)
central nervous system (CNS)
Peripheral nervous system (PNS)
nuclei vs ganglia
nuclei= cell bodies in CNS (similar structure & function)
ganglia= cell bodies in PNS (similar structure & function)
what makes up the CNS
what makes up the PNS?
cranial and spinal nerves
what are cranial nerves
emerge from brain and go to structures
what are cranial nerves?
emerge form brain and go to spinal cord
3 main subdivisions of the brain
what is the forebrain composed of
2 massive cerebral hemispheres and diencephalon
what separates the 2 cerebral hemispheres?
(medial) longitudinal fissure
are there more neurons or glial cells in the brain??
MORE GLIAL CELLS
how many neurons in the brain
100 billion neurons
how many glial cells in the brain
1 trillion glial cells in brain/spinal cord and PNS
what are neurons
information processing and signalling elements
used to convey information (electrical signals)
3 major components of a neuron
1) cell body/soma
function of cell body/soma?
supports metabolic and synthetic needs of neuron
function of dendrites?
- they are tapering processes
function of axons?
conducts information AWAY from cell body
- long, cylindrical processes
what are sensory neurons
either directly sensitive to various stimuli, or receive direction connections from non-neuronal receptor cells
where do motor neurons end?
directly on muscles, glands or other neurons in PNS ganglia
where are the processes of interneurons
processes confined to single small area in CNS
what are projecting neurons
have long axons connecting different areas
who is Ramon Cajal?
Father of Modern Neuroscience
- neurons are individual elements
- described functional circuits
- pyramidal cell from layer 3 impregnanted with Golgi method
- small number of cells get stained, able to differentiate structure led to identification of different cell types
what is Cajal famous for?
Golgi Technique & Silver stain
what are synapses
location where neurons COMMUNICATE with each other
- input= dendrite
- output= axon
what is neuroanatomy?
describes connections between neurons that lead to pathways and circuits that subserve specific functions
3 types of neuroglial cells
3) ependymal cells
3 types of MACROGLIA
3- Schwann Cell
2 types of astrocytes and associated with?
protoplasmic= associated with neuron CELL BODIES (gray matter)
fibrous= associated with dendrites and axons, processes of neurons (white matter)
function of astrocytes
- regulate exchange of molecules
- contributes to BBB
- regulate blood flow
- contribute to structural integrity of nervous tissue (structural support)
- sense/monitor neural activity