Unit 6 Patho Flashcards
What are the Glia cells in the CNS?
Oligodendrocytes
Astrocytes
Ependymal
Micoglia
What are the Glia cells in the PNS
Schwann
Satellite
What are the two parts of a synapse?
Presynaptic (Axon terminal) and
Postsynaptic (Membrane of other cell)
Which neurocrine primarily act on a synapse and elicit rapid responses?
Neurotransmitters
Which neurocrine act on both synaptic and non-synaptic site and act more slowly?
Neuromodulators
Which neurocrine secretes into the blood and are distributed throughout the body?
Neurohormones
Which neurocrine-Amines play a role in allergic reactions in addition to serving as a neurotransmitter acting on reception the brain?
Histamine
Which two neurocrine-Amines influence attention, motivation, wakefulness, movement, and memory?
Serotonin and Dopamine
Which Neuro-Amines are major neurotransmitters of the PNS autonomic division controlling smooth and cardiac muscles, glands, and the CNS?
Epinephrine and Norepinephrine
Which Neurocrine-Amino acid is primarily excitatory neurotransmitter in the CNS?
Glutamate
Which Neurocrine-Amino Acid is the main inhibitory neurotransmitter in the CNS?
GABA
One presynaptic neuron branches to affect a larger number or postsynaptic neurons is an example of which pathway?
1) Convergent Pathway
2) Divergent Pathway
Divergent Pathway
Many presynaptic neurons provide input to influence a smaller number of postsynaptic neurons is an example of which pathway?
1) Convergent Pathway
2) Divergent Pathway
Convergent Pathway
What are the 3 classifications of a nerve injury?
Neuroplasia
Axonotomesis
Neurotomesis
What happens if the cell body (soma) of a neuron is damaged?
The neuron would not regenerate
What happens if the axon of a neuron or if the terminal branches gets damaged?
They can regenerate and the speed of the growth is about 1 millimeter per day
What happens during neuroplasia?
Demyelination and the axon is still intact, but the myeline sheath is compressed. (Least severe)
What happens during Axonotomesis in nerve injury?
Demyelination and Axon loss, the endoneurium is still intact and the neuron can still regrow. However the axon terminal will die. Undergoes wallgrian degeneration.
What happens during Neurotomesis in nerve injury?
Demyelination, axon loss, damage to the endoneurium ( Fair growth), perineurium (poor growth), epineurium (No growth)
What is the difference between a weak stimulus and a strong stimulus? In terms of action potential.
The frequency of an action potential firing indicates the strength of a stimulus.
Weak stimulus release little neurotransmitter.
Strong stimulus cause more action potential and release more neurotransmitter.
What is slow synaptic potential in the postsynaptic responses?
The second messenger system use to create slow synaptic potentials and long term effect.
What is fast synaptic potential in the postsynaptic response?
When ion channels open directly by neurotransmitters on receptor channels for rapid, short acting effects.
Depolarizing synaptic potentials are called:
Excitatory postsynaptic potentials (EPSP)
[Makes cell more likely to fire action potential]
Hyperpolarizing synaptic potentials are:
Inhibitory postsynaptic potentials (IPSP)
[Less likely to fire action potential]
What is temporal summation?
Temporal summation occurs when two graded potentials from one presynaptic neurons occur close together in time.
What is the difference between no summation and summation causing action potential in a Temporal Summation?
No summation: is when two subthresholds graded potentials will not initiate an action potential if they are far apart in time.
Summation causing action potential: Is when two subthresholds potentials arrive at the trigger zone within a short period of time. They sum up and initiate an action potential.
What is synaptic inhibition, what occurs?
One inhibitory postsynaptic potential (IPSP) sums with two excitatory postsynaptic potentials (EPSPs) to prevent an action potential in the postsynaptic cell.
Describe the sequence of events during the generation of an action potential.
The action potential begins with a resting state, ➡️ it then involves depolarization (influx of sodium), it reaches a threshold opening the voltage gated sodium channels. [This causes a rapid incline causing membrane potential to spike] ➡️ it then goes to a repolarization state (due to potassium efflux) ➡️ it then restores to the resting membrane