Term
name concentration gradients of the following ions:
Na+
K+
Cl- |
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Definition
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Term
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Definition
E = 62log(co/ci)
or E = RT/zF log(co/ci) |
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Term
| give the goldman equation |
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Definition
| E = RT/F Log((pK[K+]o + pNa[Na+]o + pCl[Cl-]i)/(pK[K+]i + pNa[Na+]i + pCl[Cl-]o)) |
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Term
| when can K+ concentrations increase? |
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Definition
| during excercise: K+ is released from the exercising muscle. |
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Term
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Definition
stays relatively constant even during hyper and hypokalemia. This is very important to keep normal neurological function!
Hyperkalemia is potentially life threatening because of the heart arrythmias it causes. KCl is the 3rd and final injection given during lethal injection. |
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Term
| what is the 'unstable potential threshold'? |
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Definition
| the threshold at which action potentials will fire 50% of the time: i.e. IK+ = INa+ |
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Term
| what does tetrodotoxin do? |
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Definition
blocks Na+ channels
other drugs that do this are: lidocane, carbamazepine (anticonvulsant), and quinidine (antiarrhythmic) |
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Term
| which subunit of voltage gated Na+ channel is voltage-sensitive? |
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Definition
| S4. it has many + charged AA that act as a voltage sensor. |
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Term
| GEFS (generalized epilepsy with febrile seizures plus), SMEI (severe myoclonic epilepsy of infancy), ICEGTC (idiopathic childhood epilepsy with tonic-clonic seizures), IS (infantile spasms), CGE (cryptogenic generalized epilepsy), and SIGEI (severe idiopathic generalized epilepsy of infancy) are all caused by... |
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Definition
| mutation in the voltage gated sodium channel |
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Term
| an axon 1 um in diameter and 1 m long has the same electrical resistance as... |
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Definition
1010 miles
of 22-guage copper wire ___ the length of wire 10 times the distance from here to Saturn |
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Term
| what is the time constant determined by? |
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Definition
| the product of RmxCm. it is usually around 10-50 ms |
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Term
| what is length constant determined by? |
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Definition
| Sqrt(Rm/Ri). usually around 1-2mm in neurons |
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Term
| pathology of MS and guillain berre |
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Definition
| demyelination in the CNS, PNS respectively |
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Term
| examples of type I neurons: |
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Definition
alpha motor, Ia and Ib (spindle and golgi tendon organs, respectfully)
they are large-diameter (12-20) and myelinated |
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Term
| example of type II neurons: |
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Definition
axons to intrafusal fibers (gamma),
Meissner corpuscles, Merkel endings and Pacinian corpuscles (A-beta)
they are intermediate diameter (6-12um) and myelinated |
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Term
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Definition
sharp pain, cold, touch, hair cells (delta or A-delta)
preganglionic autonomics (type B)
they are small diameter (1-6um) myelinated |
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Term
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Definition
slow pain, heat, itch, some touch (type C)
postganglionic autonomics
small diameter (<1.5 um) and unmyelinated |
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