Term
| What is the difference between action potential in a skeletal muscle fiber versus a heart muscle fiber? |
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Definition
| In a skeletal muscle the action potential is limited to one fiber, but since cardiac muscle produces rhythmic coordinations of contraction the action potential spreads to adjacent fibers through gap junctions of intercalated discs. |
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Term
| True or False: The motor nerve contacts skeletal muscle cells at three point, at the beginning, middle, and end of the fiber. |
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Definition
| False, it contacts it at one point and it is variable. |
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Term
| Why are skeletal muscles multinucleated? |
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Definition
| Because the form from the fusion of myoblasts. |
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Term
| Briefly describe the process of muscle contraction starting with the motor neuron. |
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Definition
| Ach is released, depolarizes end plate of muscle fiber and propagates the length of the fiber, depolarizes T-tubules, releases Ca in SR, Ca binds to troponin, tropomyosin has conformational change and shows binding sites on actin, energized myosin+ADP+Pi bind to actin, causing muscle contraction, myosin gets fresh ATP to release binding site and bind again. |
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Term
| How is calcium taken back up into the sarcoplasmic reticulum? |
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Definition
| An ATP dependent calcium pump. |
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Term
| What is key to maintaining a muscle contraction in regards to calcium level in the muscle cell. |
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Definition
| The contraction will stay maintained as long as internal calcium levels are elevated. |
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Term
| What is the tool called that measures membrane permeability as a function of transmembrane voltage and time? |
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Definition
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Term
| What is the difference between inward and outward current with respect to the membrane potential? |
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Definition
| Inward- positive charge moving into the cell, outward- positive charge moves out |
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Term
| The H&H blocker studies revealed that the early and late phases of membrane current after depolarization are due to what? |
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Definition
| Na+ and K+ selective conductance through their respective independent pathways |
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Term
| What does this equation describe in regards to membrance potential: I^ion=g^ion(Vm-E^ion)? |
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Definition
| The relationship between the ionic current(I^ion), the conductance(g^ion), and driving force (Vm-E^ion, which is the voltage - equilibrium potential). |
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Term
| True or False: the key discovery of membrane conductance was that upon depolarization there was a fast activation of Na+ conductance, fast deactivation of Na+, and a slow K+ activation. |
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Definition
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Term
| What do akrasia and teleological mean? |
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Definition
| Acting against your better judgement; the philosophical study of design and purpose. |
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Term
| What is the resting membrane potential of a cell and by how much does it change when it depolarizes? |
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Definition
| -65mv, approx. 100mv towards positive voltage (+40mv) |
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Term
| Since action potentials are all or none events and they propagate without decrement, how much change in voltage is necessary to cause depolarization? |
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Definition
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Term
| After an action potential there is a brief absolute refractory period during which another action potential can not be triggered, what is this period called? |
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Definition
| Absolute refractory period, which limits firing frequency to 1000hz. |
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Term
| True or False: The amplitude of the action potential can vary depending on the strength of the stimulus. |
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Definition
| False, it is an all or none event. |
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Term
| What is it that the Goldman-Hodgkin-Katz equation figures out in regards to membrane potential? |
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Definition
| The resting membrane potential in Voltage factoring relative concentrations of 2 different ions. |
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Term
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Definition
| Slow depolarization of a membrane may not cause an AP because Na+ channels inactivate and K+ channels open. |
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Term
| What are the differences between cardiac and skeletal muscle AP’s? |
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Definition
| skeletal muscle AP triggers contraction while cardiac AP controls duration of contraction, cardiac AP’s are also much longer and have Ca+ channels contribute to the AP shape. |
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Term
| True or False: All action potentials are the same. |
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Definition
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Term
| True or False: action potential requires only active current flow. |
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Definition
| False, both passive and active. |
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Term
| Why is that there is faster conductance for thicker axons? |
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Definition
| Internal resistance decreases. |
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Term
| True or False: the difference in speed of signal conduction in myelinated versus unmyelinated axons is small but significant. |
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Definition
| False, the difference is large and significant, 10m/s vs 150m/s |
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Term
| What are the two types of synapses and what are their main features? |
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Definition
| Electrical- AP current can flow freely between cells, in both directions, due to gap junctions, seen in heart cells; Chemical- calcium regulated neurotransmitters induce AP, seen in brain |
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Term
| True or False: these are criteria for a neurotransmitter - stored in vesicles with molecular machinery, calcium-dependent, it has a receptor in postsynaptic cell, have enzymes or transporters to terminate their actions after release. |
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Definition
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Term
| What is the basic summary of the classic neuromuscular junction experiments? |
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Definition
| Basically, Katz found that the chemical messengers were quantized and that you could create many subthreshold events happen at the junction without an AP response. |
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Term
| With low frequency firing in chemical synapses, what is preferred as a signal molecule - small molecules or peptides? |
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Definition
| Small molecules first, then as signaling becomes exhaustive then both released as internal concentration of Ca+ increases |
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Term
| Which responds faster, a ligand gated ion channel or a G-protein coupled receptor? |
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Definition
| Ligand gated channel, in about 1ms vs .1-1s |
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Term
| Which ion are nicotinic channels permeable to, Na+ or K+? |
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Definition
| Normally both, they are non-selective cationic channels, so its ability to hyper or depolarize depends on resting membrane potential |
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Term
| True or False: Ligand gated ion channels are composed of these families - nicotinic, glutamate, and P2X. |
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Definition
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Term
| What is the enzyme that degrades Ach in the postsynaptic membrane? |
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Definition
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Term
| In the Physician’s Charter, what are the 3 principles describes as fundamental, universal, and definitive? |
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Definition
| Primacy of patient welfare, patient autonomy, social justice. |
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Term
| In PBL case 1, Nikhil was diagnosed with B-thalassemia major, a disorder with malfunctioning Hb, what happened on day 2? |
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Definition
| The mother went through IVF several times to get an embryo without the defect and a good HLA match so that they could use the cord blood for Nikhil. In real life the IVF was blocked by courts of England. |
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Term
| In PBL case 2, baby bryce was exposed to Accutane by his dumb ass teenage mother, the ultrasound showed no abnormalities, what happened on day 2? |
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Definition
| The retinoic acid severely disrupted normal brain formation causing extensive neurological and developmental problems. |
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Term
| In PBL case 3, Herman was hospitalized after heat exposure, he had high levels of chloride in his sweat, and he had a long history of lung infections, what happened on day 2? |
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Definition
| His genetic tests confirmed that he had CF but a mild version, his brother had extensive genetic testing for his wife and himself and found that their child was only a carrier of CF. |
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Term
| In PBL case 4, Mr. Markov had extreme reactions to ricin poison, he soon died from the shock and coursing poison, what happened on day 2? |
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Definition
| The doctors realized that there was nothing that they could do because there is no antidote, ricin blocks ribosomal translation of proteins, and the only option would to stabilize his symptoms. |
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Term
| In PBL case 5, Ms. Collins returns from Haiti with odd, irregular mole formation, she has them biopsied and given a path report with bad news, what happens on day 2? |
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Definition
| She goes on chemo to attempt to stop the metastasis of the carcinoma but it was too late and the cancer went to her brain, so she stopped chemo because of its limited bioavilability, she then died. |
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Term
| In PBL case 6, Sam shows severe and multiple infections and isn’t responding to normal antibiotics and is found to have Nocardia, what happenes on Day 2? |
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Definition
| He is diagnosed with CGD because his respiratory burst was negative, showing that his immune system could phagocytize pathogens but not kill them. |
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Term
| In PBL case 7, dude had a bad, dry cough that kept getting worse, what happened on day 2? |
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Definition
| He was diagnosed with Mycobacterial Tuberculosis, quarantined for a period and given an extensive therapy of antibiotics both in the hospital and to take home for six months. |
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Term
| What is pharmacovigilance? |
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Definition
| The science of understanding and preventing adverse effects of drugs. |
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Term
| For pharmacovigilant rates of frequency, what is the prevalence in a population of adverse effects if it is deemed - very common, common, uncommon, rare, very rare? |
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Definition
| 1/10, 1/100, 1/1000, 1/10,000, >1/10,000 |
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Term
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Definition
| Adverse effects from medical treatment or advice |
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Term
| What is enzyme inhibition? |
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Definition
| Two drugs competing for the same enzyme |
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Term
| What changes the most with geriatric pharmacology and what should you do - absorption, distribution, metabolism, elimination? |
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Definition
| Metabolism and elimination slow the most and so you should lower the dose. |
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Term
| What is the difference between relative and absolute contraindication? |
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Definition
| Relative refers to a condition which makes a particular treatment slightly inadvisable(X-rays) whereas absolute refers to a treatment that is completely inadvisable(aspirin). |
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Term
| What is the difference between a primary resource and a secondary one? |
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Definition
| Primary is creating a new data set and findings, secondary is summaries of primary studies like textbooks as meta-analysis. |
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Term
| What is the difference between an observational study and an experimental study? |
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Definition
| Observational is case series/control or cohort studies, experimental is clinical trials and they are the preferred method to answer clinical questions |
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Term
| How many half lives does it take to reach 90% of steady state? |
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Definition
|
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Term
| What is the equation for bioavailability (F)? |
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Definition
| (AUC parenteral/enteral dose)/AUC IV dose |
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Term
| What is the equation of volume of distribution? |
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Definition
| Vd=dose/plasma concentration(Cp) |
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Term
| What is the equation for half-life? |
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Definition
|
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Term
| What is the equation for clearance? |
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Definition
| Cl=(rate of elimination/Cp)=.693*Vd/t(1/2)=k*Vd |
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Term
| What is the equation for concentration at steady state(Css)? |
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Definition
|
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Term
| What is the equation for loading dose? |
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Definition
|
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Term
| What is the equation for maintenance dose? |
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Definition
| Maintenance dose=Css*Cl*time interval |
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Term
| Describe the structure of the sarcomere and what happens to the A bands and I bands upon contraction. |
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Definition
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Term
| Describe the relation of calcium to tropomyosin and the myosin head. |
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Definition
|
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Term
| Describe how movement of K+ ions in a cell are related to the balance of membrane potential and equilibrium potential for an ion. |
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Definition
|
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Term
| describe the overall structure of a muscle fiber and notice that the T-tube and the SR get close next to the A-I band junction. |
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Definition
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Term
| Understand the following image, including inactivation and time delays. |
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Definition
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Term
| Understand the following from the picture that follows: negative charges attract K+ to pore, the pore helix draws K+ to filter, backbone carbonyl oxygens help K+ shed its water, mutual repulsion between K+ ions moves them through selectivity filter. |
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Definition
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Term
| Review image: the reason saltatory conduction works is because it insulates leaky channels and allows the flow of action potentials to jump from node to node versus channel to channel. |
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Definition
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Term
| Image review: The key point of this is that repolarization is due to a decrease in Na+ and an increase in K+, and that during this time another AP cannot be generated because the h gates are closed. |
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Definition
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Term
| Understand the basics between the two synapses in the following image. |
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Definition
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Term
| Understand the details of the chemical synapse in this image. |
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Definition
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Term
| Know the difference between ligand-gated ion channels and G-protein coupled receptors, using this image. |
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Definition
|
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Term
| What does positive current refer to? |
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Definition
| Positive charges moving out of the cell, negative charges move in. |
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Term
| True or False: the Na/K ATPase plays a vital role in the action potential. |
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Definition
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