- Membrane Potential
- Action Potential
- Synaptic Physiology
- Autonomic Physiology
- Metabolic Fuel Sources in the Fed & Fasting States
- Glycolysis and PDH
- TCA Cycle and Anaplerotic Reactions
- ETC, Oxygen Reduction, and Redox Biochemistry
- Gluconeogenesis & Glycogen Metabolism
- Cell Death and Differentiation
1. 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?
No because Northerners have excess brown fat reserves
Yes because they feel warm because their body is vasodialating causing heat to leave their skin
No, because hoes don’t get cold
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
2. Which of the following would be a long-term effect of hemolytic anemia?
Increase in erythropoietin
Increase in 2,3-BPG
Increase in bicarbonate
3. Which of the following is an example of a positive feedback mechanism?
Liver pyruvate kinase activity is up-regulated by fructose-1,6-bisphosphate
Stretch receptors in the cervix signal the pituitary to release oxytocin
Lactate is transported out of muscle tissue so that muscle lactate dehydrogenase can continue to recycle NAD+ against a low product concentration gradient
Pyruvate dehydrogenase is inhibited by acetyl-CoA
4. Gene 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 a hormone that is secreted from the pituitary gland causing him to not 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 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 not 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 pressure
5. Jenna 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
- Returning to homeostasis
- Anticoagulant response
- Anti-inflammatory response
6. Which 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 = -90, Eanion = -100
Vm = -70, Ecation = -80
Vm = -90, Ecation = -120
Vm = -70, Eanion = -100
Vm = -90, Eanion = 80
7. Potassium 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.
Sodium is negatively charged so it sticks to the positively charged sides of the channel.
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 too small to pass through the channel so it diffuses through without a channel.
8. Lethal 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 excessive action potentials which shock the heart until it stops working
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 excessive action potentials which shock the heart until it stops working
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 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
9. Patent 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 depolarizes the membrane because there is no Na/K pump action because there is a lack of ATP
It hyperpolarizes the membrane because there is an influx of K making it harder to reach threshold
It causes the threshold to increase meaning it takes a bigger stimulus and makes it harder for oxygen to be transported throughout the body
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.
10. Cystic Fibrosis is a disease caused by a mutation in which of the following types of channels?
Mechanically gated chloride channels
Ligand gated calcium channels
Ligand gated chloride channels
Voltage gated chloride channels
Voltage gated calcium channelsAnswer C.
11. The ion with the biggest effect on the resting membrane potential is the ion with
The largest driving force
The most voltage gated channels
The highest permeability
The least net movement
The greatest negative charge
12. A patient presents at a clinic you are rotating at during your OMS III year with acute hyperkalemia. Which of the following is a true statement regarding the physiology of this condition?
There is more potassium in the extracellular environment, so the driving force of the ion has gone up.
There is more potassium in the extracellular environment, so the membrane potential will depolarize
There is more potassium in the extracellular environment, so the membrane potential will hyperpolarize
There is less potassium in the extracellular environment, so the membrane potential will depolarize
The potassium concentrations has remained the same, but the membrane will depolarize
13. Which of the following locations has voltage gated calcium channels?
Axon HillockAnswer B.
14. An unknown bacteria has the following equilibrium potentials for sodium and potassium (picture above). Given these values, what is the driving force of potassium? Would it flow in or out? Assume the membrane potential of this bacteria is -60.
24, flow outward
-24, flow inward
-128, flow outward
128, flow inward
-60, no net movement
15. Which of the following is true regarding the Sodium Potassium ATPase?
It pumps 3 Potassium in
It pumps 2 Sodium out
It is responsible for the gradients that allow glucose uptake in the small intestine
It is responsible for depolarization
It uses ATP to drive ions with their concentration gradientsAnswer C.
16. Adrenoleukodystrophy is a rare hereditary metabolic disorder in which fats accumulate in the brain causing demyelination of nerves. Which of the following symptoms would you expect to see in a patient suffering from adrenoleukodystrophy?
17. In reference to the diagram above, which segment is dominated by the opening of ligand gated sodium channels?
18. You are completing your residency as a family practitioner and one of your colleagues asks for a refresher on coding for stimulus intensity. You explain that the intensity of the stimulus is impacted through
The length of time it fires
The strength of the action potential
The conduction speed
19. Which of the following descriptive factors can be used to describe an action potential?
Inhibitory or ExcitatoryAnswer D.
20. While rotating in the ED your preceptor notices a patient come in with a superficial laceration to their forearm and instructs you to suture the wound. Before you begin suturing you inform your patient you are going to inject Lidocaine (a local anesthetic) into the area around the laceration to numb the area. If you want to really be a know-it-all you can explain that the lidocaine will inhibit which of the following from working?
Ligand gated sodium channels
Voltage gated sodium channels
Ligand gated potassium channels
Voltage gated potassium channels
Voo dooAnswer B.
21. Tristan drinks Diet Coke at all hours of the day averaging about a twelve pack daily. Lately he has been having headaches and drinking more because he believes they are caffeine related headaches. What problem is he truly having?
The caffeine is causing a blockage of acetylcholinesterase which is causing his neuromuscular junctions to fire constantly causing the headaches
Diet Coke contains MSG which causes a short-term reaction that results in headaches
An ingredient in the Diet Coke activates NMDA receptors and turns phenylalanine into a toxic intermediate causing headaches
Diet Coke contains a lot of sugar and the headache he is getting is from his body becoming used to that amount of sugar and then using it quickly
The Diet Coke opens calcium channels that then cause a cascade of reactions, these reactions running all at once cause his head to hurt as it goes into overdrive
22. What is the correct order of the sequence of events of action potential propagation?
1. Neurotransmitters bind to postsynaptic receptor
2.Voltage gated Ca2+ channels open,
3. Neurotransmitters diffuse into synaptic cleft
4. Na+ channels open in postsynaptic neuron,
5. Threshold is reached initiating a new action potential
6. Neurotransmitter is degraded by enzymes in the synaptic cleft,
7. Ca2+ influx
8. Synaptic vesicles fuse with membrane,
9. Action potential reaches the presynaptic terminal,
9, 2, 7, 5, 6, 8, 3, 1, 4
5, 6, 9, 2, 7, 8, 3, 1, 4
5, 9, 7, 2, 6, 1, 8, 3, 4
9, 2, 7, 8, 3, 1, 4, 5, 6
9, 4, 2, 7, 8, 1, 3, 6, 5
23. Sinemet (Carbidopa-levodopa) is a medication used to treat the symptoms of parkinson’s disease. How does this medication work?
It increases dopamine production
It decreases dopamine breakdown
It increases dopamine release
It inhibits MAO
It inhibits COMT
24. The synapse responsible for a sodium channel causes a graded potential could be described as which of the following?
Chemical Excitatory Ionotropic
Chemical Excitatory Metabotropic
Electrical Inhibitory Ionotropic
Chemical Inhibitory Metabotropic
Electrical Excitatory IonotropicAnswer A.
25. You recently discover that one of your grandparents has been diagnosed with Alzheimer’s Disease. Knowing that Glutamate excitotoxicity has been found to be correlated with this disease, what else may also be dysfunctional?
Inability for calcium influx
Nitric oxide synthase
Adenylyl CyclaseAnswer A.
26. Why are blood vessels able to contract strongly and not contract in a ripple?
They do not require an action potential
They release an excess of calcium so they contract very fast
They do not have synaptic clefts to get across
Neurotransmitters are always firing
Their nerves are highly myelinated
27. When we are hot, our body sends a signal to our sweat glands to release their contents which then evaporates on our skin to help cool us down. Which of the following explains how the sweat gland functions?
The preganglionic neuron releases acetylcholine which then activates a nicotinic receptor that releases acetylcholine onto a muscarinic receptor that releases acetylcholine to activate the sweat gland
The preganglionic neuron releases acetylcholine which then activates a muscarinic receptor that releases acetylcholine onto a nicotinic receptor that releases acetylcholine to activate the sweat gland
The preganglionic neuron releases norepinephrine which then activates a nicotinic receptor that releases acetylcholine onto a muscarinic receptor that releases acetylcholine to activate the sweat gland
The preganglionic neuron releases norepinephrine which then activates a muscarinic receptor that releases acetylcholine onto a muscarinic receptor that releases acetylcholine to activate the sweat gland
The preganglionic neuron releases acetylcholine which then activates a nicotinic receptor that releases norepinephrine onto a muscarinic receptor that releases acetylcholine to activate the sweat gland
28. Mike is college basketball player. He goes in for a checkup and finds that his heart rate is resting at about 45 beats per minute. He had just learned that 60-100 beats per minute is normal and is concerned about his low rate. You tell him that:
Because of his athletic build, he doesn’t need his heart to pump as hard to profuse his tissues
Because of his muscle tone, he has an excess of myoglobin which is able to release O2 to his tissues so his heart doesn’t need to pump as hard
He has an increased vagal tone meaning that it takes more sympathetic stimulation to raise his heart rate
He has a decreased vagal tone meaning that it takes more sympathetic stimulation to raise his heart rate
He has a decreased vagal tone meaning that it takes more parasympathetic stimulation to raise his heart rate
29. Which of the following is true in regards to the sympathetic nervous system?
It is predominately activated in times of minimal stress
The preganglionic fibers enter the grey rami communicates before exiting the white
Its preganglionic neurons predominately come from the brain stem
Its postganglionic neurons only release norepinephrine
It has long postganglionic neuronsAnswer E.
30. While doing your family medicine rotation 3rd year you notice a patient with who has been diagnosed with both high blood pressure and asthma. It looks like your preceptor may not have noticed he was diagnosed with both because when you look at his chart he has been prescribed which of the following medications?
Beta 1 Blocker
Mixed Beta Blocker
Beta 2 Agonist
Alpha 1 agonistAnswer B.
31. A patient recently had to have both his adrenal glands removed due to adrenal cell carcinoma. Which of the following activities would it be most difficult for him to achieve now?
Bronchiole smooth muscle constriction
Increased GI Motility
Increased heart rate and contraction
Thermoregulation due to sweatingAnswer D.
32. Which of the following Cranial Nerves is NOT attributed to the parasympathetic nervous system?
Oculomotor (CN III)
Facial (CN VII)
Glossopharyngeal (CN IX)
Vagus (CN X)
Hypoglossal (CN XII)Answer E.
33. Which of the following is true regarding the autonomic tone of blood vessels?
Supplied only by sympathetic
Supplied only by parasympathetic
Mixture of both but dominated by sympathetic
Mixture of both but dominated by parasympathetic
Does not have autonomic toneAnswer A.
34. Assume for the point of this question that the heart follows the concept of the Denervation in the same principle as blood vessels. After the heart has been completely denervated the heart rate will increase to that of the sinoatrial node which is 80-100. After one week a patient is given an epinephrine injection due to an allergic reaction What will the effect on the patient’s heart rate be?
There will be no effect since denervation means the removal of all receptors
The heart rate will decrease slightly
The heart rate will decrease dramatically
The heart rate will increase slightly
The heart rate will increase dramaticallyAnswer E.
35. Which of the following below correctly matches the receptor with its G protein/mechanism of action?
Alpha 1 – Gi
Beta 1 – Gq
Beta 2 – Gs
Nicotinic – Gs
Muscarinic 2 – GqAnswer C.
36. Which of the following below correctly matches the reflex with its stimulus and response?
Urination – distention of the bladder causes contraction of the internal urinary sphincter
Coughing – irritation of the respiratory tract causes explosive inhalation of air
Baroreceptor – sudden rise in carotid blood pressure causes reduction in heart rate and force of contraction
Cardioacceleratory – sudden decline in carotid blood pressure causes reduction in heart rate and force of contraction
Pupillary – bright light shinning in the eyes causes constriction of pupils in both eyesAnswer C.
37. The preganglionic axons that synapse with collateral ganglia of the abdominopelvic cavity are most specifically
Axons to the adrenal medulla
Sympathetic chain ganglia
Parasympathetic chain ganglia
38. You are rotating in your OMS III year with a neurologist that asks you about your knowledge of preganglionic axons. You tell him that they all communicate with the neurotransmitter:
39. Raynaud’s Phenomenon is a condition where cold activates the sympathetic nervous system and results in a scenario of excessive vasoconstriction. This is most commonly seen in the hands, feet, ears, nose, and other extremities. What would be the most effective medication to use to treat such a condition?
40. Alpha 2 receptors differ from the other receptors in the adrenergic class in which it belongs. Because of this variation, they prevent excessive stimulation so that you do not have a heart attack each time you are scared. They can perform this life saving response because when Alpha 2 receptors bind norepinephrine
The preganglionic neuron releases acetylcholine, exciting the postganglionic neuron
The preganglionic neuron hyperpolarizes, decreasing acetylcholine release and postganglionic neuron activity.
The preganglionic neuron depolarizes, increasing acetylcholine release and postganglionic activity
The cell acts with positive feedback and promotes excessive sympathetic output
There is no change in the preganglionic neuron, so the postganglionic neuron functions as normal
41. When doing a biopsy of your diabetic patient’s pancreas, you discover that your patient has cancer in their β-cells. You then get a measurement of her C-peptide and your preceptor asks why that is a logical next step. You tell him that:
It will let you know if it is benign or malignant
It will determine how much insulin she is producing
It will determine if they are injecting the correct amount of insulin
It will allow you to see if and where the cancer has metastasized to
It will determine if the pancreas is functioning as it should to help with digestion
42. Your friend Tiffany was only half listening about leptin and is confused as to why it couldn’t be used independently to treat obesity in humans. Which of the following explains why this would not be an effective obesity treatment for humans?
Leptin is only found in mice
Leptin alone couldn’t work, it would have to be used in conjunction with peptide Y which has not been purified and isolated
Leptin is already secreted, its signal is ignored by individuals and eventually they become leptin insensitive
Leptin is already secreted, but it is less efficient when there is more adipose tissue
Leptin is only released when exercising, so giving it to obese patients would not be effective unless they are active.
43. After running a routine physical and blood tests on a patient, they begin to freak out because their blood glucose level is 135! They are very healthy, non obiese 35 year old male, and have no history of diabetes in their family. What is the most likely cause of the high blood glucose levels?
They may be pregnant and developed gestational diabetes
They have developed a mutation and have started to become a type 1 diabetic
They are so sensitive and sweet to other people they just have a normally elevated blood glucose level
They drink too much diet soda with aspartame which is known to raise blood glucose levels
They didn’t listen like most people and ate 2 hours before their examAnswer E.
44. Martha tells you that she has been doing the keto diet where she eats fewer than 20 grams of carbohydrates a day. While on this diet, what does her red blood cells use for fuel?
They will switch to using ketone bodies to run glycolysis
They will function on the 20 grams of carbohydrates that she consumes per day
They will rely more heavily on gluconeogenesis to create glucose
They will switch to using fats to create energy through β-oxidation
They will break down amino acids from the increased protein she is consuming.
45. Epinephrine is a more powerful regulator of glycogen synthesis/breakdown than glucagon, which is why it needs two different receptors on the liver. When epinephrine bings to a Beta 2 receptor on the liver, which G protein will it be?
46. The conversion of Fructose-6-Phosphate to Fructose-1,6-Bisphosphate is a highly regulated part of glycolysis. Which of the following is an agonist of this step?
47. Which of the following pairs would show a similar Lineweaver-Burke graph?
Hexokinase, GLUT 2
Glucokinase, GLUT 2
Hexokinase, GLUT 4
Glucokinase, GLUT 4
48. Which step in glycolysis is unable to proceed if there is a shortage of NAD+?
Step 1 – glucose → glucose-6-phosphate
Step 3 – fructose-6-phosphate → fructose-2,6-bisphosphate
Step 6 – glyceraldehyde-3-phosphate → 1,3-bisphosphoglycerate
Step 9 – 2-phosphoglycerate → phosphoenolpyruvate
Step 10 – phosphoenolpyruvate → pyruvateAnswer C.
49. Veronica suffers from anorexia nervosa causing her to have low vitamin B1 levels. Which of the following coenzymes related to the pyruvate dehydrogenase complex would she have trouble synthesizing?
50. Which of the following regulators when present will decrease or inhibit the formation of Acetyl CoA from Pyruvate by activating PDC Kinase?
51. Fumaric aciduria is a rare autosomal recessive metabolic disorder characterized by a deficiency of the enzyme fumarate hydratase (fumarase), which causes a deficiency of malate. What effect would this have on the production of ATP?
This would cause a build up of oxaloacetate in the mitochondria
This would cause glycolysis to not be able to occur in the mitochondria
This would cause glycolysis to not be able to occur in the cytoplasm
This would cause the electron transport chain to collapse
This would cause oxaloacetate to be converted to malate at a slower rate
52. Isocitrate dehydrogenase is the TCA enzyme responsible for the oxidative decarboxylation of Isocitrate to 𝝰-ketoglutarate. In IDH mutations, mutant isocitrate dehydrogenase additionally reduces 𝝰-ketoglutarate to D-2-hydroxyglutarate (2-DHG). How does this mutant TCA oncometabolite compromise cellular integrity that potentially leads to cancer?
2-DHG through feedback inhibition ceases the enzymatic activity of Isocitrate dehydrogenase.
2-DHG competitively inhibits 𝝰-ketoglutarate dependent dioxygenases.
2-DHG allosterically activates succinate dehydrogenase to produce metastatic levels of 𝝰-ketoglutarate.
2-DHG irreversibly activates 𝝰-ketoglutarate dependent dioxygenases that generate onco-enzymatic proteins that promote unregulated cell proliferation.
53. The legend of vampires is believed to have stemmed from individuals who had the disease porphyria which can often include symptoms such as sensitivity to sunlight which can be treated with exogenous blood ingestion. Deficiency in which TCA cycle intermediate can lead to porphyria?
54. Which of the following enzymes reduce a vitamin B2 derivative through their enzymatic activity in the TCA cycle?
55. Which of the following below contains the three enzymes that produce NADH during the TCA Cycle?
Isocitrate dehydrogenase, ɑ-ketoglutarate dehydrogenase, Succinyl-CoA synthase
Succinate dehydrogenase, Isocitrate dehydrogenase, Succinyl-CoA synthase
Malate dehydrogenase, Isocitrate dehydrogenase, Succinate dehydrogenase
Malate dehydrogenase, Isocitrate dehydrogenase, ɑ-ketoglutarate dehydrogenase
Malate dehydrogenase, ɑ-ketoglutarate dehydrogenase, succinate DehydrogenaseAnswer D.
56. In the early 1960’s the benefits of Vitamin E were discovered and doctors started prescribing it as a pill to virtually everyone. Which of the following explains why this was not effective in preventing many of the diseases that natural vitamin E had been seen to prevent?
Most of the patients had scurvy so the were unable to turn the free radicals into the aqueous form and therefore unable to rid the body of them.
Vitamin E supplements were only one form of tocopherols and when they were taking the pills, they were depleting the other forms thus unable to oxidize in other ways.
Vitamin E must be taken as a part of a multivitamin or else it depletes the other vitamins and causes more harm than good
Even if they had the increased Vitamin E, they would still have the same amount of Glutathione so they would be unable to oxidize the radicals.
In larger doses, vitamin E actually causes more free radicals to form.
57. Molly’s pediatrician told her that she could give acetaminophen to her 6 month old for fevers. She didn’t have any acetaminophen so she gave her baby baby aspirin which she thought would be okay because it had the word baby in the name. Which of the following explains what would happen?
Her baby’s fever would decrease because aspirin and acetaminophen are interchangeable and you can use them at alternating times
Her baby’s fever would decrease because the aspirin would work to block the COX1 and COX2 pathways
Her baby’s fever would decrease because the aspirin would work to block the 5-LOX pathway
Her baby’s fever would spike because aspirin would uncouple the ETC causing heat instead of ATP to be formed.
Her baby would die because aspirin would decrease the infant’s ability to clot so they would bleed out.
58. In most infections (especially bacterial), neutrophils are characterized as the first responders as they often the first leukocyte to be elevated and attempt to resolve the infection. Neutrophils are also characterized as phagocytes which means they ingest their targets and then fuse them with lysosome to degrade them. Phagocytes also implement reactive oxygen species is order to damage and destroy their ingested targets. Which NADPH oxidase (NOX) enzyme is found in these types of cells?
NOX 5Answer B.
59. Nitric oxide is created in endothelial cells of blood vessels when acetylcholine binds to its G protein coupled receptor. What enzyme will the G alpha subunit activate after acetylcholine has bound?
Nitric Oxide SynthaseAnswer C.
60. Kevin wanted to look cool when he went to his first rave festival, so he took amphetamines that he got from the sketchy looking man in the bathroom line. Unfortunately they were laced with MPP+ and Kevin woke up confused in the hospital with tremors in his hand, stiff muscles, and feeling very fatigued. Which of the following explains his symptoms
The MPP+ caused complex I of ETC to not work
The MPP+ caused complex II of ETC to not work
The MPP+ caused complex III of ETC to not work
The MPP+ caused cytochrome C of ETC to not work
The MPP+ caused Coenzyme Q of ETC to not work
61. Which of the following is required to produce additional NADPH in order to fuel Glutathione Reductase to reduce glutathione?
62. People suffering from Khron’s Disease are frequently deficient in many vitamins including Selenium due to their inability to absorb vitamins despite their consumption. Which of the following would be affected by a selenium deficiency?
Superoxide dismutase I
Superoxide dismutase II
63. People with hemolytic anemia have problems reducing glutathione. Hemolytic anemia results in the rupture of red blood cells. Which of the following would NOT be a problem for people with this disease?
They are not able to regenerate NADPH
They get a buildup of H2O2 in their cells
They get a buildup of hydroxyl radicals
They get a buildup of NADPH
They have a reduced number of RBCs
64. Which of the following would be an example of a Hormetic response to stressors?
65. In the very young and the elderly, it is common to be deficient in the various B vitamins. If one of these individuals is deficient in both cobalamin and pyroxidine, they will get a toxic buildup of which product?
Methyl Malonyl CoA
66. All of the following Gluconeogenic mechanisms are stimulated by increased levels of Glucagon, except for:
Phosphorylated Pyruvate Kinase
Increased PEPCK gene transcription
Increased hepatic Fructose 2,6-bisphosphate
67. Skipping her normal balanced breakfast, Tammy was beginning to feel the burn one hour in to her midmorning marathon in downtown Chicago. Which of the following occurs during Glycogenolysis to maintain Tammy’s blood glucose levels and fuel exercising skeletal muscle during this event?
Phosphorylation of Glycogen Phosphorylase by PKA
Phosphorylation of Glycogen Synthase by Glycogen Phosphorylase
Phosphorylation of Glycogen Phosphorylase by Phosphorylase Kinase
Phosphorylation of Phosphorylase Kinase by Glycogen Phosphorylase
Phosphorylation of Glycogen Synthase by Phosphorylase Kinase
68. A point mutation in glycogenin causes a stop codon to form where a tyrosine residue should be. Which of the following would you expect to see in a patient with this mutation?
Inability to convert glucose-6P to glucose 1P
Inability to convert glucose-1P to glucose-6P
Inability to form glucose chains of glycogen
Inability to form the branch points of glycogen
Inability to break the glucose free from the glycogen chains.
69. A mutation in PFKFB genes 1-4 on chromosome X leads to non-functional PFK-2/FBP-2 enzyme. What effect does this have on metabolism?
Inability to carry out glycolysis because fructose-1,6-bisphosphate cannot be synthesized from fructose-6-phosphate.
Inability to metabolize fructose.
Inability to carry out glycolysis because fructose-2,6-bisphosphate is necessary for the activity of PFK-1/FBPase-1
Simultaneous gluconeogenesis and glycolysis
PFK-2/FBPase-2 is not responsible for producing fructose-1,6-bisphosphate, nor does it metabolize fructose (fructokinase). Fructose-2,6-bisphosphate is a regulator of PFK-1/FBPase activity, but is not a necessary cofactor.
70. Which of the following would best depict or be characteristic of Glycolysis?
Increased FBP-1 activity
Phosphorylated (PFK-2/FBP-2) enzyme
PFK-1 product modulating Pyruvate Kinase activity
Increased FBP-2 activity
Decreased PFK-1 activity
71. In order to test the efficacy of a novel drug therapy on diseased cardiomyocytes, you first want to determine if any unwanted side-effects occur in otherwise healthy cardiac cells. Fibroblasts donated to your research clinic from a healthy 30 year old male could be reprogrammed into iPS cells using which of the following combinations of transcription factors?
c-Myc, Nanog, Oct4
Oct4, Sox2, c-Myc
Sox2, Oct4, Axin
Wnt, Oct4, Klf4
Klf4, Sox2, Oct4
72. A patient comes in complaining of pain in their lower abdomen. Blood tests are ordered and show an increase in white blood cells. A CT scan reveals a tumor in their small intestine. Which of the following enzymes involved in the WNT pathway would you expect to see a mutation in?
73. Which of the following is a difference between necrosis and apoptosis?
Apoptosis is cell death whereas necrosis is cell resurrection
Apoptosis occurs with individual cells whereas necrosis occurs with multiple cells
Necrosis requires a signal whereas apoptosis occurs on its own
Necrosis is programmed cell death whereas apoptosis occurs because of injury or disease
Necrosis occurs because of stress whereas apoptosis is a natural part of the cell cycle
74. Following an MI there is an increase in neutrophils that can be seen in tissue samples of myocardial tissue, which of the following explain this?
An MI is due to an infection in the heart and these cells are trying to rid the body of the infection
An MI causes death of myocardial tissues via apoptosis which causes inflammation as the cells rupture
An MI causes death of myocardial tissues via necrosis which causes inflammation as the cells rupture
This would only be seen in patients with an autoimmune disease in which their neutrophils attack healthy cells
This would not occur.
75. After a routine follow-up visit, your patient presents you with information regarding a new stem cell therapy for DM Type I that they saw on Doctor Oz using earlobe cartilage as a stem cell precursor. As a DM Type I patient, they intrigued and clearly fixated on this new therapy as a way to cure their life-long disease. As an osteopathic physician trained in bioethical practices and well-versed in current stem cell literature, you politely inform your patient that:
Only stem cell therapy derived from skin fibroblasts and driven to the iPS cell state by the core trio are considered legitimate therapies approved by the FDA for use in the U.S.
Although questionable, SC therapy derived from ear cartilage that undergoes the appropriate processing are FDA approved as the infancy of this therapy has not yet been proven as detrimental to patient health beyond a reasonable doubt.
The only stem cell-based products that are FDA-approved for use in the U.S. consist of hematopoietic progenitor cells derived from cord blood.
No form of stem cell-based products are FDA-approved as the infancy of this technology negates it from being a legitimate therapy until epidemiological methods have been used to compile and analyze the current data.
76. A tissue sample from an unknown skin lesion is analyzed microscopically and enzymatically to determine whether or not necrosis has taken place. Which of the following scenarios is indicative of necrosis and not apoptosis?
Immunofluorescence assay indicating phospholipid phosphatidylserine exposed on the outer leaflet of the cell membrane.
Free LDH present in the blood of the tissue sample.
Segmented and condensed nuclear chromatin.
Free IL-10 and TGF-β present in the blood of the tissue sample.
77. Your patient, a seasoned automotive mechanic, presents to your clinic with an abnormal growth on his forearm that occasionally bleeds and has persisted for the past 6 months. During the intake, he reveals to you that he has never felt the need to wear protective gloves while doing oil changes for the past 30 years. You biopsy the lesion and send it to pathology to rule out basal vs. squamous cell carcinoma. What abnormality in the internal cell death program would indicate that apoptosis has been compromised in this lesion?
Cytochrome-c occupies all of the available sites of Apaf-1, activating the protein.
p53, a tumor suppressor protein, binds to its response element within DNA and results in suppressed transcription of the target gene.
Bax embeds itself in the mitochondrial membrane and facilitates the release of cytochrome-c.
p53, a tumor suppressor protein, binds to its response element within DNA and induces transcription of the target gene.
78. A recent discovery by John B Gourdon and Shinya Yamanaka showed that mature cells can be reprogrammed to become pluripotent using a specific set of transcription factors that are able to upregulate and downregulate thousands of genes depending on their concentrations. Which of the following transcription factors is unable to reprogram cells by regulating epigenetics?
79. Mesenchymal cells of the mesoderm are considered to be which of the following?
80. The inner cell mass is considered to be pluripotent because it can become almost everything necessary to a developing embryo and future human. What is one structure that it can NOT become?
Epithelium of the respiratory tract
Anterior Pituitary Gland
Right Lobe of the LiverAnswer C.