Final Lecture Exam Flashcards
What are the different types on neurons
Multipolar (most common, in brain/spinal cord)
Bipolar (in retina)
Unipolar (sensory organs/spinal cord nerve)
Anaxonic (brain/helps in visual processes)
Describe axonal transport
2 way passage of proteins, organelles, and other material along an axon
Difference. Between anterograde and retrograde
Ante: movement down axon away from soma
Retro: movement up the axon to the soma
What do microtubules do
Guide materials along axon
What are the 6 diff glial cells
CNS: oligodendrocytes (form myelin sheath)
Ependymal cells (lines internal cavities, secrets cerebrospinal fluid)
Microglia (small, wandering macrophages formed by monocytes)
Astrocytes (supportive framework)
PNS: Schwann cells (envelope nerve fibers)
Satellite cells (surround neurosomas)
What are the differences between Schwann cells and oligodenrocytes
Schwann cells are in PNS, assist in regeneration of damaged nerve fibers and spirals repeatedly around a single nerve fiber, oligodenrocytes are in the CNS and form myelin sheaths anchored to multiple nerve fibers
What are nodes of Ranvier, internodes, and trigger zone
N.O.R.: gap between segments
Internodes: myelin covered segments from one gap to the next
Trigger Zone: the axon hillock and the initial segment (initiates nerve signal)
How do unmyelinated nerve fibers work
Travels up to 2 m/sec
How do myelinated nerve fibers work
Travels faster than unmyelinated
How do large nerve fibers work compared to small nerve fibers
Large work up to 120 m/sec while small work >/= 15 m/sec
What is the process of regeneration of nerve fibers
Needs regeneration tube in the PNS system
What is a regeneration tube
Formed by Schwann cells (PNS), basal lamina, and neurilemma near the injury
What is denervation atrophy
Muscle loss of nerve contact by damaged nerve
What are local potentials characteristics
Graded, decremental, reversible
What are action potentials characteristics
Follows an all or none law, nondecremental, irreversible
What is hyperpolization
When membrane potential becomes negative
What are the two types of refractory period and when do they occur
Absolute: from action potential to RMP
Relative: RMP to hyperpolarization
What is saltatory conduction
The never signal seem to jump from node to node
What are pre and post synaptic neurons
Pre: 1st neuron in signal path, contains synaptic vesicles that have the neurotransmitter
Post: 2nd neuron, constrains proteins that fxn as receptors and ligand regulated ion gates
What are the four major categories of neurotransmitters
- Acetylcholine
- Amino acid neurotransmitters
- Monoamines
- Neuropeptides
What are the embryonic derivations of CNS (start with forebrain, midbrain, hindbrain)
4th week they appear
5th week: forebrain divides into 2 (telencephalon/diencephalon), midbrain remains mescencephalon, hind brain divided into 2 (metencephalon/myelencephalon)
What’s the general structure of gray/white matter, Cortex, and corpus callusum
Gray: neuron cell bodies, dendrites, synapses, dull white
White: bundles of axons, lies deep to gray, pearly white
Cortex: made of gray matter, surface layer
Corpus Callosum: thick nerve bundle at bottom of longitudinal fissure
What is rostral and caudal
Rostral: toward forehead
Caudal: toward spinal cord
What are the layer of meninges and their distinctive features
- Dura mater: no epidural space, not attached to bone, layers separated by dura sinuses (outer periosteal: equivalent to periosteum of cranial bones, inner meningeal: continues into vertebral canal and forms dura sac around spinal cord)
- arachnoid mater: transparent membrane
- pia mater: very thin membrane that follows contours of brain
