Neuro Flashcards
Afferent
Sensory info - propagates input from the periphery to the CNS
Efferent
Motor info - propagates input from the CNS to the periphery/muscle
White Matter (Brain)
Composed of primarily axons & myelin (made from lipids) & forms the bulk of the deep parts w/in the brain
Serves to connect the various cell bodies to one another
Grey Matter (Brain)
Composed of mainly nerve cell bodies & glial cells & is distributed over the surface of the brain, as well as within the brain nuclei
Nissl Granules
scattered through the cytoplasm of a neuron; composed of rough endoplasmic reticulum w/free ribosomes & are responsible for protein synthesis/cell metabolism
synapse
site of transmission between the axon of one nerve and dendrites of another
motor end plate
site of transmission between an axon and a muscle
Neurolemma
composed of Schwann cells which envelop axons for myelinization of the PNS
Oligodendroglia
responsible for the myelinization of the CNS using the combination of: basic myelin protein + proteolipid protein
What are the types of glia in the CNS?
- astrocytes
- oligodendroglia
- microglia
Roles & Function of the Astrocyte
- function: supportive scaffolding for the neurons of the CNS
- neurotransmitter reuptake
- neuronal metabolism (esp. CHO/sugars)
- help form/regulate/maintain BBB w/pseudopodic extensions surrounding outer capillary wall
Blood Brain Barrier
- highly selective barrier that separates circulating blood from the CSF & is composed of tight nit capillary walls & astrocyte extensions
- provides a protective barrier to the brain for local immune function
Permeable substances to the BBB
O2 CO2 amino acids small sugars lipid-soluble substances (general anesthetics)
Most common CNS tumor in the US?
astrocytomas
Microglia
- protectors of the CNS: derived from monocytes & macrophages
- remain dormant until activated by mechanical, chemical, or immunologic injury –> phagocytize cells –> cytokine release
- implicated in Alzheimer’s & other dementias
Ependymal cells
line the central canal of the spinal cord & brain ventricles; involved in CSF production
What are the (5) part of the brain?
- Telencephalon
- Diencephalon
- Mesencephalon
- Metaencephalon
- Myencephalon
Telencephalon
highest center of the brain
composed of: cerebral hemispheres & basal ganglia
Cerebral hemispheres
Contain most of the mass of the brain & the outer convex surface is made up of gyri
Hemispheres are separated by sulci but connected centrally at the corpus callosum
Which 2 brain landmarks divide the brain into 4 ares?
The lateral fissure & central sulcus divide the cerebrum into 4 lobes (frontal, parietal, temporal, occipital)
Which gyrus makes up the limbic lobe?
Cingulate gyrus - located above/superior to the corpus callosum
What makes up the corpus callosum?
commissural fibers - connect the hemispheres of the brain
What connects the lobes of the brain and the gyri to one another?
associative fibers - long & short fibers connect lobes to each other & also the gyri together
Internal capsule
- anterior limb & posterior limb connected by genu
- made up of projection fibers
- the major route by which the cerebral cortex is connected w/brainstem & spinal cord
- white matter that separates the caudate nucleus & thalamus from the lenticular nucleus
