CNS- Functions in the Brain Flashcards
What is the limbic system comprised of
the septal nuclei, olfactory bulbs, thalamus, hypothalamus an hippocampus
what are the functions of the limbic system
learning, emotion, sex, appetite, endocrine integration/hormonal control
what are the layers of the meninges
Dura mater–> tough outer layer
Arachnoid layer–> spidery intermediate mesh
Pia mater–> delicate inner layer
what is meningitis
infection of the meningies
what is the CSF
made in the brain ventricles and reabsorbed into venous blood
what are the functions of the CSF
it maintains an electrolyte balance around neurons and bathes and supports the neural tissue
what is hydrocephalus
known as “water in the brain” it happens when reabsorption is blocks and the CSF accumulates in brain, treated via drainage tubes surgically
what are the functions of astrocytes
physically supports the neurons, forms a blood-brain barrier, repairs and forms scar tissue, recycles neurotransmitter molecules, maintains an electrolyte balance
what is the function of oligodendrocytes
forms myelin sheath in the CNS which electrically insulates acons
what is the function of ependymal cells
produce CSF
what is the function of microglia
ingest bacteria and debris known as scavengers
what are brain tumors
not from neuronal cells
arise from proliferation of aberrant glial cells–>Gliomas
or from meninges–>meningiomas
what is the blood brain barrier(BBB), what glial cell is important for its formation
the capillaries in the CNS are less porous compared to the rest of the body, glial cell–> astrocytes
what are the functions of the BBB
protection–> protects neurons from chemical fluctuations and harmful agents
provides oxygen and glucose(brain doesn’t have glycogen stores)
selectively transports molecules needed by brain(like glucose) while excluding harmful substances(hormones, ions, etc.)
impacts drug delivery
how is drug delivery maintained in BBB
precursor drugs are used, very small molecules that get converted into needed drug
L-dopa–> dopamine for Parkinson’s
efferent vs. afferent
efferent
motor, CNS–> muscles
afferent
sensory, PNS–> CNS
somatic vs. autonomic divsion
somatic–> voluntary
autonomic–> involuntary
what are sensory receptors
afferent axon that goes to the CNS
located in the dorsal root ganglion
enters spinal cord and stops with synaptic connections on interneurons and efferent neurons
what do the efferent neurons do
the axons innervate effector organs like muscles and glands
