Master BECOM 1 Exam 2 QBank Published on July 30, 2020 by David Leonard BECOM 1 Exam 2 (2018) Click "Next" to continue Which of the following is occurring at the point in the graph depicted by the red arrow? Na+ inactivation gates are closed Na+ activation gates are open None of the above K+ inactivation gates are opening K+ activation gates are closingIschemic strokes occur when the arteries to your brain become narrowed or blocked, causing severely reduced blood flow. Which of the following best describes how a patient’s ETC would be affected if they were experiencing a stroke? The lack of blood flow would directly inhibit the function of Complex II and cause a subsequent release of reactive oxygen species from Complex I and II The lack of blood flow would directly inhibit the function of Complex IV and a subsequent release of reactive oxygen species from Complex I and III The lack of blood flow would directly inhibit the function of Complex III and cause a subsequent release of reactive oxygen species from Complex I and III The lack of blood flow would directly inhibit the function of Complex IV and cause a subsequent release of reactive oxygen species from Complex I and II The lack of blood flow would directly inhibit the function of Complex I and cause a subsequent release of reactive oxygen species from Complex IDamage to the ETC by means of cyanide poisoning would lead to leakage of electrons through which channels? Complex III Complex I and III Complex II Complex IV Complex ILauren, an OMS I student, is celebrating her outstanding performance on the anatomy exam by hitting the dance floor at the Electric Cowboy (she’s got Flossing down!). She realizes that she forgot to eat dinner, but doesn’t want to leave to grab a meal. She opts to pile on the drinks because, after all, alcohol has carbohydrates and she’ll be satisfied (at least for a little bit). How will her body respond? NADH levels will decrease but rapidly start increasing Initial hypoglycemia, but soon her body will become hyperglycemic Lowering the activity of aldehyde dehydrogenase Increasing gluconeogenesis Initial hyperglycemia, but soon her body will become hypoglycemicThe ganglionic blocking drug hexamethonium, which antagonizes N2 receptors, is administered intravenously. Which of the following would be most likely to be observed in response to administration of this drug? Tachycardia, decreased blood pressure Bradycardia, decreased blood pressure Tachycardia, increased blood pressure Tachycardia or bradycardia equally likely, increased or decreased blood pressure also equally likely Tachycardia or bradycardia equally likely, decreased blood pressureWhich of the following would be a long-term effect of hemolytic anemia? Increase in erythropoietin Increase in 2,3-BPG Bohr effect Haldane Effect Increase in bicarbonateThe autonomic nervous system has many global targets across both sympathetic and parasympathetic pathways. Which of the following is dually innervated by both of these divisions? Coagulation cascade Cardiac muscle Sweat glands Arteriolar smooth muscle KidneysWhich of the following is an activator of pyruvate kinase in the liver? ATP None of the above Fructose-1,6-P GTP AlanineYou are doing rotations in the Emergency Department when a 25-year-old female patient is brought in via ambulance. The paramedics tell you that she is in anaphylaxis due to a bee sting. You’re a super smart med student, so you know that anaphylactic shock is associated with systemic vasodilation that causes low blood pressure. Which of the following would be the best course of action in order to fix this associated vasodilation and drop in blood pressure? You should administer a low dose of epinephrine since α-receptors have a higher affinity for Epinephrine than that of ß-receptors You should administer a low dose of epinephrine since α-receptors have a lower affinity for Epinephrine than that of ß-receptors You should administer Viagra You should administer a high dose of epinephrine since α-receptors have a lower affinity for Epinephrine than that of ß-receptors. You should administer a high dose of Epinephrine since α-receptors have a higher affinity for Epinephrine than that of ß-receptors.In preparation for board game night, Seth and Ed each brought their favorite snacks to enjoy throughout the night. Shortly after eating all of his doughnuts, Seth was already hungry again. Ed, however, was still feeling quite content after eating his quinoa and mushrooms. What is the likely cause for this discrepancy? Seth’s doughnuts have a high glycemic index, causing a large, but short spike in blood glucose Seth’s donuts had a high abundance of Fructose, causing glycolysis to occur unchecked and create an abundance of ATP Seth’s doughnuts absorb at a slower rate, so he isn’t getting as much energy from them The fructose content in Ed’s quinoa was converted to fat, which has twice the calories of carbs, it’s simple science. Ed’s quinoa has a high glycemic index, causing a prolonged spike in blood glucoseWhich division of the autonomic nervous system has the shortest postganglionic distance? Parasympathetic muscarinic Sympathetic muscarinic Parasympathetic cholinergic Nicotinic 1 motor plate Sympathetic cholinergicWhile epinephrine by nature has a global effect on several sympathetic adrenergic receptors, upon its initial release, to which receptor type with it bind to preferentially? β2 β1 β3 α2 α1Which part of a K+ channel subunit is primarily responsible for K+ selectivity over Na+? S6 (inner helix) S5 (outer helix) Hyrophospate end P segment Alpha binderDenervation supersensitivity describes that after denervation of a cell, the loss of available neurotransmitter causes the cell to… Up-regulate receptors, in essence looking for transmitters Learn to respond to different neurotransmitters Experience necrosis from lack of stimulation Become less sensitive to other nerves that innervate it Regrow the nerves from the cell endLethal injections contain potassium chloride which works to stop the heart. Why is this an effective method of euthinasia? It causes Na gates to remain inactive which means it cannot return to resting membrane potential causing cessation of action potentials making the heart unable to pump It causes K gates to remain open which means it cannot return to resting membrane potential causing cessation of action potentials making the heart unable to pump It causes Na gates to remain inactive which means it cannot return to resting membrane potential causing excessive action potentials which shock the heart until it stops working It causes more potassium to be in the extracellular fluid making it harder for the cell to reach threshold so there is less action potentials being reached and thus the heart stops beating It causes K gates to remain open which means it cannot return to resting membrane potential causing excessive action potentials which shock the heart until it stops workingIn someone infected by the Clostridium botulinum bacteria, there is a complete blockade of a key neurotransmitter to the respiratory muscles. By what means does the botulinus toxin produce this fatal effect? Blocking the release of acetylcholine at the presynaptic terminals Blocking the acetylcholine receptors at the motor plate Inhibition at the site of the postsynaptic muscarinic receptors Inhibiting the action of acetylcholine esterase Depletion of acetylcholine at the presynaptic terminalA neuron fires an action potential. From that we know that: Neurons are magic and they fire when they feel like it. The neuron received enough excitatory inputs to fire an action potential even if inhibitory inputs were received as well. The neuron received a balance of excitatory inputs and inhibitory inputs but that the excitatory inputs were closer to the axon hillock. The neuron received only excitatory inputs. The neuron received only inhibitory inputs.With extreme parasympathetic stimulation present in situations like organophosphate poisoning, you would expect which symptoms to be ABSENT? Muscle spasm Miosis Defecation Increased cardiac force of contraction Extreme salivationGene was recently diagnosed with hypertension and put on enalapril, an ACE inhibitor. He wants to know how it works, so you tell him, in layman's terms: It blocks an enzyme that prevents a hormone that tells the body to not absorb water thus decreasing blood pressure It blocks a hormone that is secreted from the pituitary gland causing him to not absorb water thus decreasing blood pressure It blocks a hormone that is secreted from the pituitary gland causing him to absorb water thus decreasing blood pressure It blocks an enzyme that prevents a hormone that tells the body to absorb water thus decreasing blood pressure It blocks the formation of Renin which then prevents the body from creating a hormone called aldosterone which thus decreases blood pressureAs a third year medical student, your resident shows you a patient file showing a confirmed diagnosis of chronic granulomatous disease, which is caused by an enzyme mutation in NOX-2. Where is this enzyme located that it would lead to symptoms associated with this condition? Extracellular membrane Intracellular phagosome membrane This is cause by a free enzyme in the cytosol The inner mitochondrial membrane The outer mitochondrial membraneThe conversion of Pyruvate to Acetyl CoA is regulated by all of the following EXCEPT: Acetyl CoA FADH2 NAD+ FADH2 CoASHAn action potential can serve many functions in the body, what are some of the effects of blocking an action potential? Cellular response to allow for muscle contraction and neurotransmitter release Blocking in sensory nerves can allow for analgesic effects Information delivery to the central nervous system The cell will always remain depolarizedThe glycolytic enzyme PFK-1 would have decreased function under which of the following conditions? Mutation resulting in decreased activity at the ATP effector binding site High concentrations of AMP Low concentration of citrate High concentrations of ATP High concentrations of F-2,6-BPWhat is TRUE about fructose metabolism? Conversion of fructose-1 phosphate to fat is a highly regulated process Regulation of fructose is accomplished by PFK-2, which converts fructose 1-phosphate into fructose 2,6-bisphosphate Fructose enters glycolysis after the key regulatory step, allowing it to go unchecked and produce an abundance of fat in the liver The relatively high ratio of glucose to fructose in high fructose corn syrup is what makes the substance so bad for you It’s the most efficient fuel source for ATPWhen there is a bloodborne infection, cells of the immune system produce vast amounts of nitric oxide to destroy the pathogen. This dilates blood vessels and can cause blood pressure to plummet – a condition called septic shock. Which of the following is an additional reason for why an accumulation of NO could be dangerous? A & C Excess amounts of nitric oxide can react with free oxygen radicals forming peroxynitrite (ONOO-) Peroxynitrites (ONOO-) can break down into Nitrogen dioxide radicals (•NO2) and hydroxyl radicals (•OH) B & C Excess amounts of nitric oxide can react with superoxide radicals forming peroxynitrite (ONOO-)Which of the following enzymes is involved in a reaction unique to gluconeogenesis? Phosphoglycerate kinase Phosphoglyceromutase Pyruvate carboxylase Phosphoglucose isomerase Phosphofructokinase-1Which of the following is an example of a positive feedback mechanism? Pyruvate dehydrogenase is inhibited by acetyl-CoA Lactate is transported out of muscle tissue so that muscle lactate dehydrogenase can continue to recycle NAD+ against a low product concentration gradient Stretch receptors in the cervix signal the pituitary to release oxytocin Liver pyruvate kinase activity is up-regulated by fructose-1,6-bisphosphateOrthostatic hypotension occurs when a person’s blood pressure falls when suddenly standing up from a lying or sitting position. It occurs predominantly by delayed constriction of the lower body blood vessels, which is normally required to maintain an adequate blood pressure when changing position to standing. As a result, blood pools in the blood vessels of the legs for a longer period and less is returned to the heart, thereby leading to a reduced cardiac output. This is an example of: Negative Feedback Low Gain System None of the Above High Gain System Positive FeedbackPatent ductus arteriosus is a heart defect in the pulmonary artery that carries oxygen-poor blood to the lungs and the artery that carries oxygen-rich blood to the rest of your body. How would this condition affect the rest of the body in terms of membrane potential? It hyperpolarizes the membrane because there is an influx of K making it harder to reach threshold It repolarizes the membrane before there is an action potential, so the body cannot effectively carry oxygen throughout the body It would not affect membrane potentials, it would have an effect on hemoglobin binding causing a shift to prefer myoglobin. It depolarizes the membrane because there is no Na/K pump action because there is a lack of ATP It causes the threshold to increase meaning it takes a bigger stimulus and makes it harder for oxygen to be transported throughout the bodyAlbuterol is a commonly used beta 2 agonist. What physiological effect with occur upon treatment with albuterol? Increased sweat production Decrease in heart rate Inhibition of adenylyl cyclase Dilation of bronchiolar smooth muscle Constriction of vascular smooth muscleA neuron has a threshold of -45 mV. Resting membrane potential is -60 mV. A depolarization stimulus of 10 mV is applied. What is the effect? The neuron will depolarize however an action potential will not fire There will be no effect The neuron will hyper-polarize An action potential will fire Initially, the neuron will hyperpolarize but then it will depolarizeStimulants, colloquially referred to as “uppers,” are drugs that increase activity of the central nervous system by eliciting sympathomimetic effects. Which of the following is most likely a symptom of someone who had taken a stimulant? Profuse sweating Increased digestion Miosis Reduced blood pressure Decreased heart rateVon Gierke disease, is the most common of the glycogen storage diseases. This genetic disease impairs the ability of the liver to produce free glucose from glycogen and from gluconeogenesis. A deficiency in which of the following enzymes would lead to this disease? PFK-1 PEPCK Glucose-6 Phosphatase Pyruvate carboxylase deficiency 2,3-BPG mutaseTonic control regulates physiological parameters in an up-down fashion. Match the effects of the neurotransmitter and the correct nervous system with its associated physiological effect. Decreased norepinephrine for the sympathetic nervous system would cause a decrease in signal rate and therefore blood vessel dilation to cause an increase in blood pressure Decreased norepinephrine for the sympathetic nervous system would cause a decrease in signal rate and therefore blood vessel dilation to cause a decrease in blood pressure Increased acetylcholine would be present for the sympathetic nervous system and cause vasoconstriction and therefore hypoventilation Increased acetylcholine would be present for the parasympathetic nervous system and cause vasoconstriction and therefore hyperventilation Increased norepinephrine for the sympathetic nervous system would cause a decrease in signal rate and therefore blood vessel dilation to cause a decrease in blood pressureWhen there is an increased stimulus, there is an increased frequency in action potential firing. What are some of the effects this could have? Greater neurotransmitter release from axon terminal which causes a greater target response Change in amplitude of the action potential The neuron will hyper-polarize A, B Increased acetylcholine release in synaptic cleft causing a greater depolarization of cell to cause more frequent firing and greater calcium release A, CThe market for antidepressants and antipsychotics in the pharmaceutical industry is massive, with many drugs targeting the serotonergic synapse. Which of the following would be a viable method for relieving the symptoms of depression at this site? Selective deactivation of the 5-hydroxytryptophan decarboxylase enzyme Consuming a diet low in tryptophan Upregulating the expression of monoamine oxidase (MAO) Inhibition of re-uptake by monoamine transporters Inhibition of pre-synaptic 5-HT storageOnce a vessel is damaged, platelets start to cling to the injured site and release chemicals that attract more platelets. The platelets continue to pile up and release chemicals until a clot is formed. Blood clotting is an example of: Low Gain System High Gain System None of the Above Positive Feedback Negative FeedbackEmily is a 62-year-old obese female BP=186/92, resting HR=72 bpm. She is a very sedentary, non-smoker. You diagnose her with hypertension. As her primary care physician, you prescribe the beta-1 antagonist metoprolol for treatment of her condition. Metoprolol will help lower Emily’s blood pressure through all of the following EXCEPT? Arterioles: decreased arteriolar vasoconstriction Heart: decreased heart rate Heart: decreased force of contraction Kidney: decreased renin release Kidney: decreased water conservationAhsan, a mentally exhausted medical student, decided to take a study break and go for a hike at Devil’s Den. He accidentally travelled off the beaten path when he heard some unusual noises coming from the brush. Luckily Ahsan is a highly trained eagle scout and recognized the sounds immediately as the call of a cougar. He sprung into action, boldly running from the noise and flooding his body with adrenaline. Assuming that Ahsan had eaten a meal high in carbohydrates within an hour of this occurrence, which of the following is true? Epinephrine will activate a similar signaling cascade to that of Insulin, causing an activation of PKB (Akt) and subsequent phosphorylation of Glycogen synthase. Despite his high BGL, Epinephrine will work in a similar manner to that of Glucagon causing the phosphorylation of Glycogen synthase and Glycogen phosphorylase. Epinephrine will activate a tyrosine kinase receptor signaling pathway causing the breakdown of Glycogen. His high BGL would trigger a release of Insulin and the dephosphorylation of Glycogen Synthase by Protein phosphatase. Glucagon would be released causing the activation of PKA and the subsequent dephosphorylation of Glycogen synthase and phosphorylase kinase.Which branch of the nervous system is the best at quickly conducting signals to its effectors? Autonomic sympathetic muscarinic Autonomic sympathetic cholinergic Autonomic parasympathetic muscarinic Somatic motor Autonomic sympathetic adrenergicMetoprolol is a beta 1 blocker often given to patients with high blood pressure. Patients who are prescribed this medication often stop taking it because of annoying side effects. What other side effect can be contributed to the beta 1 blocking ability of Metoprolol? Excess sweating Bronchiolar constriction Rashes Dry Eyes Weight gainA patient has bloodwork done two hours after consuming a sugary drink. Since consuming the drink, the patient has consumed no other food or beverages. The patient’s blood glucose level is 163 mg/dL. What can be said about the patient? The patient is considered diabetic. The patient’s results are considered normal. The patient is considered pre-diabetic. The patient is not producing insulin. The patient is not producing insulin.Wernicke-Korsakoff syndrome is a neurological disorder characterized by mental confusion, amnesia (a permanent gap in memory), and impaired short-term memory. Which of the following enzymes would have reduced function due to this disorder? Malonate Dehydrogenase Pyruvate carboxylase Pyruvate Dehydrogenase Methylmalonyl-CoA mutase Lactate DehydrogenaseDr. Moffitt is running yet another ultramarathon. As she approaches mile 20, she decides to reach for her gel packet tucked conveniently within her fanny pack in order to get some energy. The gel packet contains a high amount of Fructose. Which of the following is true regarding Dr. Moffitt’s decision to consume this gel packet? A glucose-only gel packet would have given her the same amount of energy It’s obviously a mistake, Fructose will be converted to fat which won’t be burned in time to give Dr. Moffitt energy Since she is undergoing prolonged exercise, Dr. Moffitt is burning ATP at an high rate and therefore can utilize the Fructose without producing an abundance of fat This is a good choice since Fructose will initiate Gluconeogenesis in the liver Fructose will undergo glycolysis without being regulated, therefore her consumption of this sugar will lead to an accumulation of fat which can be burned for energyWhich of the following is correct in regards to graded potentials and action potentials? AP always have the same strength of signal and have a refractory period that must be obeyed; GP cannot have summation Graded potentials (GP) occur in the axon hillock; action potentials (AP) occur in the dendrites/cell bodies AP can be initiated with above threshold graded potentials at axon hillock; GP are initiated in ions through channels GP only occur with voltage gated ion channels; AP can occur with any type of ion channel GP and AP can both only be depolarizedOne of your patients is Type II diabetic. In order to help them increase their insulin sensitivity you recommend more frequent exercise which you expect will: Promote recruitment of more GLUT4 receptors Increase skeletal muscle of utilization of insulin during exercise only Decrease skeletal muscle utilization of insulin during rest only Increase insulin synthesis by pancreatic beta cells Lead to higher levels of insulin in the bodyAfter consuming glucose, insulin production is turned on, whereas glucagon is turned off. Which of the following is true in the fed state? Fatty acids are broken down to maintain blood glucose levels. Glycogen synthesis is stimulated by insulin and stored in the liver and skeletal muscle. Fatty acid synthesis is inhibited by glucagon to maintain blood glucose levels. Glycogen synthesis is inhibited by the increase in insulin. Lactate production is increased, resulting in an increase in glycogen synthesis.The X-linked genetic disorder known as Leigh disease presents with mortally high levels of lactic acid in the blood due to a PDH E1 defect. With this disorder, the PDH E1 subunit would most likely display difficulty binding to which essential coenzyme? Pantothenate TPP Lipoamide Lipoate FADA patient is excreting high levels of VMA (3-Methoxy-4-hydroxymandelic acid) in their urine. This would suggest high levels of which neurotransmitter(s)? Epinephrine A & B A & C Dopamine NorepinephrineYou have been having troubles lately and your OMS1 friend decides to play doctor and suggest that you seek out some natural sources for Serotonin, postulating that this will help you sleep and feel better. Of her suggestions, which one could lead to more serotonin? Dopa decarboxylase that is sold on the corner near the riverfront. Glutamate that is in MSG and can be gotten at Harps. Choline which she swears is sold by the pound at the Farmer’s Market on Saturday. Tyrosine in a supplement from Walmart. Tryptophan which is in turkey, they are on sale at Aldi. Following extreme trauma, the body would use which TCA intermediate to replace lost heme? Citrate Oxaloacetate Succinate Succinyl CoA Alpha-ketoglutarateYou are on rotations in an underserved primary care clinic when you come across a patient who can’t stop talking about the importance of antioxidants. They tell you that they researched it on “the Google machine” and that they know all there is to know about antioxidants. When asked, the patient revealed that they’ve been taking Vitamin E for the past 5 years in order to rid their body of reactant radicals. What should you tell them? Keep doing what they’re doing, Vitamin E is a great source of gamma-tocopherol which is important in ridding the body of radicals While Vitamin E is a great source of gamma-tocopherol, it doesn’t include the other “non-gamma” tocopherols which are also important in ridding the body of free radicals While Vitamin E is a great source of alpha-tocopherol, it doesn’t include the other “non-alpha” tocopherols which are also important in ridding the body of free radicals Keep doing what they’re doing, Vitamin E is a great source of alpha-tocopherol which is important in ridding the body of radicals They are mistaken and should actually be taking Vitamin D to get the effect they’re wantingIn a neuron where potassium channels are inappropriately opened, what will be the effect on the excitability of the neuron. It will be more excitable due to depolarization. This will cause a chlorine channel to open and balance out the effect. It will be unaffected because the Na/K pumps are still working. The potassium channel will reset before any effect can be noticed. It will be less excitable due to hyperpolarization.Alcoholics typically have markedly diminished function of pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase due to decreased dietary absorption of: Biotin Thiamine Riboflavin S-adenosyl methionine SuccinateWhich of the following combinations of membrane potential (Vm) and equilibrium potential (Eion) for either a cation or anion would result in an overall decrease in membrane potential if: The channel for the specific anion or cation was open and uninhibited. Concentration differences between the cytosol and EC anion/cation are negligible. Vm = -70, Eanion = -100 Vm = -90, Ecation = -120 Vm = -90, Eanion = -100 Vm = -70, Ecation = -80 Vm = -90, Eanion = 80Which of the following is true regarding the organization of the autonomic nervous system? Sympathetic preganglionic fibers are long, myelinated fibers that synapse with postganglionic fibers extremely close to the target organ Somatic motor neurons have a large diameter, allowing for them to conduct action potentials faster Arteriolar smooth muscle is only innervated by the Parasympathetic nervous system Postganglionic fibers are usually unmyelinated and thus conduct action potentials at a slower rate N2 receptors are located at the neuromuscular junctionA patient is diagnosed with hypoxia, which of the following is NOT true about the patient with regard to membrane potentials in B cells of the pancreas? Voltage sensitive Ca2+ channels are open The membrane is hyperpolarizing ATP sensitive K+ channels are open Vm is increasing Insulin is not being secretedWhich enzyme in carbohydrate metabolism works as a tight control point for both the anabolic and catabolic pathways, ensuring that glycolysis and gluconeogenesis are not both active at the same time? PFK-2 Pyruvate carboxylase FBPase-1 Phosphoglucomutase G-6-PaseHemochromatosis is a disease in which too much iron builds up in your body. The fenton reaction explains why this buildup of iron can be so dangerous. Which of the following best describes the Fenton reaction? Fe2+ can react with free oxygen, producing superoxide radicals Fe2+ can react with other metals such as Cu+ to produce hydroxide Fe2+ can react with hydrogen peroxide, producing superoxide radicals Fe2+ can react with hydrogen peroxide, producing hydroxyl radicals Fe2+ can react with free oxygen, producing hydroxidePig insulin was regularly administered to diabetic patients before the structure of human insulin was discovered. Now that the structure is known, doctors are able to administer the active portion of insulin, while still being able to measure the amount of insulin being produced by the body. Which part of human-secreted insulin is measured? A-chain B-chain C-peptide Proinsulin InsulinA patient comes to your office with kidney and liver failure. You suspect that methylmalonic acidemia might be their diagnosis which would mean that they are likely deficient in which of the following enzymes? Vitamin B12 Vitamin B5 Vitamin B3 Vitamin B1 Vitamin B2Which of the following is true regarding succinate dehydrogenase? It produces GTP in its reaction of succinate → fumarate It oxidizes NADH → NAD+ It requires Vitamin B1 (Thiamine) It requires Vitamin B7 (Biotin) It is involved in both the ETC and TCA cycleAfter consuming a high carbohydrate meal, your body begins to break down and take in the glucose from the meal and you are considered to be in the fed state. Which of the following occurs ONLY in the liver? Both C and D Production and storage of glycogen Pyruvate kinase activity decreases in response to increased amount of ATP and alanine PFK1 activity decreases in response to an increased amount of ATP & citrate Hexokinase activity decreases in response to increased amount of G-6-P in the cellAngel waddles into class one morning complaining of intense bum soreness that she says is from her CrossFit “workout” the previous evening. This soreness is in part due to the accumulation of lactate. Which of the following best explains the reasoning for why there is an accumulation of lactate during heavy intense exercise? The TCA cycle is inhibited by heavy intense exercise The Ca2+ produced from muscle contraction works to upregulate Lactate DH Pyruvate is being generated at a higher rate than it can enter the TCA cycle Lack of oxygen availability Lactate is necessary to perform GluconeogenesisFor a combination of reasons, high consumption of alcohol leads to a depletion of which carbohydrate metabolite? 1,2-bisphosphoglycerate Glycogenin Pyruvate 3-phosphoglycerate OxaloacetatePotassium channels allow for potassium to leave the cell. What prevents sodium from using this channel? Potassium is much smaller than sodium so it is able to pass based on size. Sodiums waters of hydration do not align with the selectivity filter so they do not strip the waters off Sodium does not form waters of hydration so the selectivity filter does not recognize it. Sodium is negatively charged so it sticks to the positively charged sides of the channel. Sodium is too small to pass through the channel so it diffuses through without a channel.The activity of pyruvate dehydrogenase complex is a crucial process in carbohydrate metabolism which is regulated by the activity of two enzymes. What would you expect to see in a patient with a deficiency in the PDC kinase enzyme? No change in the activity of pyruvate dehydrogenase complex compared to a person with normal amount of PDC kinase enzyme Decreased activity of pyruvate dehydrogenase complex compared to a person with normal amount of PDC kinase enzyme None of the above Increased activity of pyruvate dehydrogenase complex compared to a person with normal amount of PDC kinase enzymeGlucagon signaling will do which of the following in the target cell? Decrease cAMP levels Lower 5′-AMP levels Deactivate glycogen phosphorylase-a Activate protein phosphatase-1 Increase glucose-1-phosphate levelsWhich glycolytic intermediates have sufficient energy to drive the production of ATP via substrate level phosphorylation? 1,3-bisphosphoglycerate and phosphoenolpyruvate Glyceraldehyde 3-phosphate and 3-phosphoglycerate 1,3-bisphosphoglycerate and phosphoenolpyruvate G6P and dihydroxyacetone phosphate F1P and pyruvateCaffeine is a potent inhibitor of phosphodiesterase. Considering this, in which of the following might caffeine have a stimulatory effect? Sympathetic ganglion Vascular smooth muscle Sweat glands Presynaptic sympathetic nerve terminals CardiomyocytesA patient comes in with CO poisoning. What can be said about the likelihood (at first) of membrane threshold being reached compared to the normal? The cell is depolarized, it is less likely to reach threshold. The cell is hyperpolarized, it is more likely to reach threshold. The cell is hyperpolarized, it is less likely to reach threshold. The cell is depolarized, it is more likely to reach threshold.Which of the following is considered to be the most dangerous reactive oxygen species (ROS)? Oxygen Superoxide radical Hydroxyl radical Hydrogen peroxide Hydroxide ionHow much time does it take for glycogen to be depleted when one is in a basal state? Glycogen is never depleted since the breakdown of all fuel sources contributes to glycogen stores 4-5 hours 1-2 days 12-14 hours 24-36 hoursDuring intensive exercise, skeletal muscle metabolites are released in high amounts into the bloodstream. If unchecked, these metabolites would cause a bottoming out of blood pressure. What mechanism is in place that keeps a check on these products, stabilizing blood pressure? Sympathetic stimulation of β2 receptors Sympathetic stimulation of α2 receptors Sympathetic stimulation of α1 receptors Sympathetic stimulation of β1 receptors Parasympathetic stimulation of M2 receptorsAlkalosis has a profound effect on neurons. It is most notable in which of the following? States of hypoxia where the low oxygen reduces availability of ATP for the Na/K pumps. Cause the neuron to reverse polarity and send all action potentials back up the dendrites to their origins. B & D States of diabetic ketoacidosis which lead to coma. Epilepsy where patients will attempt to blow off CO2, hyperventilate, elevate their blood pH and induce seizuresWhich of the following is true regarding the conductance velocity of an action potential? Myelination decreases capacitance by allowing action potentials to “jump” from node to node, increasing conduction velocity Axons with smaller diameters have increase conduction velocity Myelination creates a greater surface area to allow for ion exchange across membranes Preganglionic fibers often have a slower conduction velocity as compared to postsynaptic fibers since they are unmyelinated Myelin decreases conduction velocity by providing insulination for the axonVagal maneuvers involve various techniques of stimulating the vagus nerve (CN X) in order to elicit a specific response in the autonomic nervous system. For example, health care providers may trigger the gag reflex in their patient to stimulate this nerve and provide a therapeutic effect. Which of the following is most likely the intended effect of a vagal maneuver? Decrease heart rate Miosis Decrease gut motility Bronchodilation Increase sweat productionYou are on a pediatrics rotation when a 5-year-old female patient is brought into the clinic by their mother. The patient is severely obese. However, the mother mentions that her daughter’s nutrition is good but she is constantly hungry. What is the next thing you should do? Test for brain damage within the hypothalamus Test for a Leptin deficiency Test for Type I Diabetes mellitus Refer them to a nutritionist Test for AMPK deficiencyYou are doing clinical rotations in the Emergency Department when a patient comes in who had overdosed on Aspirin. Their symptoms include hyperventilation, vomiting, dehydration, double vision, fever, and feeling faint. A resident asks you to explain the reasoning for why this patient is exhibiting a fever. What are you going to tell them? The body creates a fever in order to provide a more suitable environment for the enzymes responsible for metabolizing the Aspirin High dose aspirin works as a chemical uncoupler, producing excess heat with the associated energy release Aspirin activates UCP1 causing thermogenesis and dissipation of heat from brown adipose stores The fever due to the body’s immunological response to the overabundance of Aspirin The patient probably has an associated infection.Which of the following is a anapleurotic reaction that occurs in the TCA cycle? Lysine → Succinate Citrate → Fatty Acids Aspartate → Oxaloacetate Glutamate → citrate Succinyl CoA → HemeCystic Fibrosis is a disease caused by a mutation in which of the following types of channels? Mechanically gated chloride channels Voltage gated chloride channels Voltage gated calcium channels Ligand gated chloride channels Ligand gated calcium channelsAfter determining that your patient has pheochromocytoma, a tumor of the adrenal medulla, you order a urine test expecting elevated levels of metabolites for primarily which small molecule neurotransmitter? Acetylcholine Nitric oxide Norepinephrine Dopamine EpinephrineWhat unique property of non-alpha tocopherols makes them an essential part of a good diet? The ability to neutralize toxic NAPQI Collaborative function with ascorbate Its higher favorability for oxyradicals Its ability to inhibit COX, 5LOX and RNS Its higher concentration in tissues than alphaTJenna fell off her bike scraping her knee. This started a cascade of cellular processes: her knee started bleeding, turned red and was painful. Her broken endothelial cells release cytokines which signal thrombocytes to release more cytokines thus activating additional thrombocytes to clot and stop the bleeding. This is an example of: Feed-forward activation Feedback inhibition Anti-inflammatory response Anticoagulant response Returning to homeostasisYour friend in medical school asks why depolarizing the membrane (such as in a state of acidemia), eventually leads to fewer action potentials. The best answer is: Depolarization causes degradation of K+ channel proteins Depolarization, if prolonged, leads to inactivated Na+ channels. Depolarization has a boomerang effect and eventually leads to hyperpolarization. Depolarization makes the cell more permeable to Cl-, which eventually hyperpolarizes the membrane. Did you hear the one about global warming? It depolarizes!In the cold northern winters, you many times will see people out at bars not wearing jackets who claim that they are not cold, is this problematic? Why or Why not? Yes, because the only reason they don’t feel cold is because they are shivering which causes muscle contractions which will not regulate body temperature Yes because their parasympathetic nervous system becomes activated which shunts blood to their core causing them to feel warmer while causing frostbite No, because hoes don’t get cold No because Northerners have excess brown fat reserves Yes because they feel warm because their body is vasodialating causing heat to leave their skin87 out of Time is Up!
