The CNS Flashcards
types of cells of the NS
- the neuron
- neuroglia
types of neurglial cells
- astrocytes
- oligodendrocytes
- ependymal cells
neuron
- brains immune cells
- protect against injury and disease
astrocytes
- metabolic buffer, detoxifies
- modulate how neurons communicate
- surround blood vessels
oligodendrocytes
- produce myelin
- myelin wraps around axons as insulation
ependymal cells
- lines spinal cord and ventricles of brain
- produces CSF
where does sensory information go to in the brain
- medulla, pons, mesencephalon
- cerebellum
- thalamus
- cerebral cortex
- SC at all levels
what are effectors
- muscles or glands
- anatomical features that do the function the brain tells them to do
major levels of CNS function
- SC
- lower brain or subcortical level
- higher brain or cortical level
spinal cord level of CNS function
- upper levels send signals to SC
- SC performs functions necessary
lower brain function
- subconscious activity
- controlled by:
- medulla
- pons
- mesencephalon
- hypothalamus
- thalamus
- cerebellum
- basal ganglia
higher brain function
- done by cerebral cortex
- essential for thought processes
- cannot function by itself
cerebral cortex function
- thinking
- learning
- remembering
thalamus function
- interprets sensory messages like pain, temp, pressure
hypothalamus function
- controls homeostatic functions
- i.e. temp, respiration, HR
cerebellum function
- muscle tone
- posture
- balance
brain stem function
- HR and breathing
- plays role in consciousness
blood brain barrier
- selectively inhibits substances that reach the brain or CSF
components of the BBB
- capillaries
- astrocyte foot
- efflux transporters
role of capillaries in BBB
- have continuous tight junctions
- limit passage of most substances
astrocyte foot in BBB
- surrounds BV
- allows small and lipophilic molecules
- contributes to brain swelling
efflux transporters
- proteins
- help expel foreign substances that pass through capillaries
where does wallerian degeneration occur
in the distal axon of a severed axon
characteristics of wallerian degeneration
- swelling in distal axon
- neurofilament hypertrophy
- myelin sheath disintegrates
- axon degenerates and disappears