Task. For each question you see two explanations (A and B) of why the stated correct answer is correct. Choose the one giving the more logically valid and complete reasoning. Ignore length, fluency, and formatting; a mere restatement of the answer is worse; choose Tie if equal. Blinded: A/B order is randomised.
Your name/initials (optional):
Question 1
Jamie Roberts is playing against Australia on Saturday in the first Welsh autumn test match. He has studying medicine here at Cardiff university. One of the older year students tell you of a rumour that once playing for uni he tackled someone so hard it dislocated their glenohumeral joint. At A&E after relocation of the humerus, The F1 doc wants to check the auxiliary nerve function to see where the dislocation damaged it. What should the doctor do to check the auxiliary nerve? Option A: See if the patient has claw hands Option B: Ask the patient to try and abduct the injured shoulder against resistance all the way to right angles with the body Option C: check for wrist drop. Option D: test small abduction of the upper limb under 20 degrees. Option E: order an MRI and see if damage can be seen on the scan. The correct answer is Option B.
Explanation A The auxiliary nerve innervates the deltoid muscle. The deltoid muscle is responsible for abduction of the arm from 15 to 90 degrees. If the nerve is damaged, the patient will not be able to abduct the arm past 15 degrees. This is because the supraspinatus muscle, which is responsible for the first 15 degrees of abduction, is innervated by the suprascapular nerve. The deltoid muscle is innervated by the auxiliary nerve and is responsible for the rest of the abduction.
Explanation B The auxiliary nerve innervates the deltoid muscle. The deltoid muscle is responsible for abduction of the upper limb between 15 and 90 degrees. The suprascapular nerve innervates the supraspinatus muscle which is responsible for the first 15 degrees of abduction. The musculocutaneous nerve innervates the biceps brachii which is responsible for flexion of the elbow.
Which explanation reasons better for the correct answer?
Question 2
Noah presents with dysuria, itching, and pain during masturbation. The doctor says he has a bacterial infection which is most probably gram-positive.What is the most likely causative organism? Option A: Chlamydia trachomatis Option B: Escherichia coli Option C: Staphylococcus aureus Option D: Treponema Pallidum Option E: Trichomoniasis The correct answer is Option C.
Explanation A Staph aureus is the most likely cause as it is gram-positive and can cause these symptoms. Chlamydia trachomatis is an STI which is gram-negative. E. coli is a gram-negative bacterium which can cause UTIs. Treponema pallidum is the causative agent of syphilis and is a spirochete. Trichomoniasis is caused by a protozoan parasite.
Explanation B The symptoms are most likely caused by staph infection. The symptoms are dysuria, itching and pain during masturbation. The doctor says it is a bacterial infection which is most probably gram-positive. This rules out chlamydia, E. coli, treponema pallidum and trichomoniasis.
Which explanation reasons better for the correct answer?
Question 3
76 year old John comes to the GP for a routine blood test. The results are shown below: HBsAg: negative HBeAg: negative IgM anti-HBcAg: negative IgG anti-HBcAg: positive IgG anti-HBsAg: positive IgG anti-HBeAg: positive Which of the following correctly interprets these results? Option A: Chronic hepatitis B infection, high risk Option B: Acute hepatitis B infection Option C: Immunity to hepatitis B due to vaccination Option D: Immunity to hepatitis B due to past infection Option E: Chronic hepatitis B infection, low risk The correct answer is Option D.
Explanation A The presence of IgG anti-HBcAg indicates that the patient has been infected with hepatitis B at some point in the past. The presence of IgG anti-HBsAg indicates that the patient is immune to hepatitis B. The presence of IgG anti-HBeAg indicates that the patient is not currently shedding the virus. Therefore, the patient is immune to hepatitis B due to past infection.
Explanation B The correct answer is D! The results show that John is immune to hepatitis B due to past infection. HBsAg: negative - no hepatitis B infectionHBeAg: negative - no high risk of transmissionIgM anti-HBcAg: negative - no acute infectionIgG anti-HBcAg: positive - past infectionIgG anti-HBsAg: positive - immunity to hepatitis B due to past infectionIgG anti-HBeAg: positive - past infection
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Question 4
In the metabolism of glucose, what are the correct numbers of products of the TCA cycle produce per molecule of glucose? Option A: 4 NADH2 CO21 ATP1 FADH2 Option B: 8 NADH4 CO22 ATP2 FADH2 Option C: 6 NADH4 CO22 ATP2 FADH2 Option D: 3 NADH2 CO21 ATP1 FADH2 Option E: 3 NADH2 CO22 ATP1 FADH2 The correct answer is Option C.
Explanation A The TCA cycle is run twice per molecule of glucose. Therefore, the correct answer is C.
Explanation B The TCA cycle is run twice per glucose molecule (once per pyruvate). Per turn of the cycle, 3 NADH, 1 FADH2, 2 CO2 and 1 ATP are produced. Therefore, per glucose molecule, 6 NADH, 2 FADH2, 4 CO2 and 2 ATP are produced.
Which explanation reasons better for the correct answer?
Question 5
In One Fish, Two Fish, Blowfish, Blue Fish (the 24th episode of The Simpsons), Homer consumes toxic Fugu at The Happy Sumo, a Japanese restaurant. Fugu is the Japanese word for pufferfish, which contains the toxin TTX (tetradotoxin). What is its mechanism of action? Option A: It binds to the extracellular side of voltage-gated K+ channels. Option B: It binds to postsynaptic nicotinic acetylcholine receptors. Option C: It binds to the extracellular side of voltage-gated Na+ channels. Option D: It promotes the reuptake of acetylcholine across the presynaptic membrane. Option E: It binds to the extracellular side of voltage-gated Na+ and voltage-gated K+ channels. The correct answer is Option C.
Explanation A TTX is a sodium channel blocker. It binds to the extracellular side of voltage-gated Na+ channels, preventing the opening of these channels. This prevents the generation of action potentials.
Explanation B TTX is a sodium channel blocker. It binds to the extracellular side of voltage-gated Na+ channels, preventing the influx of Na+ that is required for the generation of an action potential. This results in paralysis and cardiac arrest.
Which explanation reasons better for the correct answer?
Question 6
A consultant has been called in to see a patient with a tumour in their lower neck. Lab testing showed a high concentration and activity rate of the enzyme Telomerase within the nuclei of the Salivary glands cells. Why may this be a good indicator that the tumour is malignant? Option A: Telomerase breaks down telomeres found at the ends of chromosomes. This leads to damage of exposed DNA and thus the formation of cancerous cells. Option B: Telomerase breaks down telomeres found in the centre of chromosomes. This leads to splitting of chromosomes which then can lead to the formation of cancerous cells via mutations that occur during DNA repair. Option C: Telomerase increases the length of telomeres found in the middle of chromosomes by adding repetitive nucleotides. This increases the likelihood of mutations within chromosomal DNA triggering the development of cancerous cells. Option D: Telomerase increases the length of telomeres found at the ends of chromosomes by adding repetitive nucleotides. This prevents the death of dividing cancerous cells. Option E: Telomerase is indirectly produced by the binding of a protein made by cancerous cells to a DNA promoter. The increased gene expression of telomerase is non-harmful to cells but merely indicates the presence of cancerous cells. The correct answer is Option D.
Explanation A Telomerase is an enzyme that increases the length of telomeres found at the ends of chromosomes by adding repetitive nucleotides. This prevents the death of dividing cancerous cells.
Explanation B Telomerase is an enzyme that adds repetitive nucleotide sequences to the ends of chromosomes. This is known as telomere maintenance. In normal cells, telomeres shorten with each division. Once telomeres reach a certain length, the cell enters senescence (a state of irreversible growth arrest) and eventually dies via apoptosis. Cancerous cells are able to maintain telomere length by producing telomerase. This allows them to divide indefinitely and avoid senescence.
Which explanation reasons better for the correct answer?
Question 7
Emily has been brought in to A&E due to a rapid onset of encephalopathy, including increased agitation and disorientation. She has clonus, hyperreflexia, dilated pupils and increased bowel sounds. She currently takes citalopram, the combined-contraceptive pill and Piriton for allergies. What would the most likely diagnosis be for Emily, based on the symptoms above? Option A: Neuroleptic Malignant Syndrome (NMS) Option B: Serotonin Syndrome Option C: Hypertensive crisis Option D: Drug intoxication The correct answer is Option B.
Explanation A Serotonin syndrome is a medical condition that occurs when there is an excess of serotonin in the body. This can be caused by an overdose of a drug, or by the interaction of two or more drugs. The symptoms of serotonin syndrome include: - Agitation and confusion - Rapid heart rate - High blood pressure - Dilated pupils - Hyperreflexia - Clonus - Increased bowel sounds - Fever
Explanation B The symptoms of Emily are consistent with Serotonin Syndrome. This is a medical emergency caused by excessive serotonin activity in the central and peripheral nervous systems. It is most likely to occur when a patient is taking two or more drugs that increase serotonin levels. Emily is taking citalopram (an SSRI) and the combined-contraceptive pill (which contains some serotonin-reuptake inhibitors). The symptoms of Serotonin Syndrome include: - Clonus - Hyperreflexia - Dilated pupils - Agitation and disorientation - Increased bowel sounds - Fever - Tremor - Muscle rigidity - Myoclonus - Seizures - Coma The treatment is to stop the offending drugs and administer an antidote, usually cyproheptadine.
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Question 8
A 25 year old woman is thrown from her horse at a local festival. On the way to hospital she becomes increasingly drowsy. Paramedics have inserted an oropharyngeal airway and have given high flow oxygen (at 40%) via a face mask because of her obstructed airway. An arterial blood gas sample is taken. Arterial blood gas analysis reveals Patients ABG values: Normal ranges: PaO2- 18.8 kPa >10 kPa (75 mmHg) on airpH- 7.19 7.35 – 7.45PaCO2- 10.2 kPa 4.7 – 6.0 kPaBicarbonate- 23.6 mmol l-1 22 – 26 mmol l-1You try to determine what acid-base disturbance this woman has in order to manage and treat her appropriately. What acid-base disturbance is suggested by her ABG results? Option A: Respiratory alkalosis. Option B: Metabolic acidosis. Option C: Respiratory acidosis. Option D: Metabolic acidosis. Option E: Mixed acidosis/alkalosis. The correct answer is Option C.
Explanation A The patient is hypoxaemic (low PaO2) and acidotic (low pH). The PaCO2 is high, which suggests respiratory acidosis. The bicarbonate is normal, which rules out a metabolic component. The patient is also receiving high flow oxygen, which would normally cause an increase in pH (alkalosis) due to the increased oxygen content in the blood. However, the patient is also hypoxaemic, which would cause a decrease in pH (acidosis) due to the increased production of lactic acid. The fact that the pH is acidic suggests that the respiratory acidosis is more significant than the metabolic acidosis.
Explanation B The patient has respiratory acidosis. The pH is low (7.19) which indicates acidosis. The bicarbonate is normal (23.6 mmol l-1) which rules out metabolic acidosis. The PaCO2 is high (10.2 kPa) which indicates respiratory acidosis. The PaO2 is also low (18.8 kPa) which is expected as the patient has an obstructed airway.
Which explanation reasons better for the correct answer?
Question 9
The limbic system is a network of cortical and subcortical regions. It is involved in emotional ad defensive behavioural responses, and the emotional component of pain. Which part of the brain, within the limbic system, is responsible for emotional memory? Option A: Hippocampus Option B: Mammillary Bodies Option C: Amygdala Option D: Prefrontal cortex Option E: Hypothalamus The correct answer is Option C.
Explanation A The amygdala is responsible for emotional memory. It is involved in the processing of emotions, particularly fear and anger. The hippocampus is involved in the formation of new long term memories, particularly those that are episodic. The mammillary bodies are involved in memory formation and are part of the Papez circuit. The prefrontal cortex is involved in executive functions, such as planning, decision making, and working memory. The hypothalamus is involved in regulating homeostasis, including body temperature, thirst, and hunger.
Explanation B The correct answer is C - the amygdala. The hippocampus is involved in the formation of new memories, and the mammillary bodies are involved in memory consolidation. The prefrontal cortex is involved in emotional regulation and the hypothalamus is involved in the autonomic nervous system.
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Question 10
Of the following combinations of vitamins, select the correct combination of water soluble vitamins: Option A: Vitamin B12Vitamin E Option B: Vitamins B,1,2,3,5Vitamin B12 Option C: Vitamins B,1,2,3,5,6,9Vitamin D Option D: Vitamins B,1,2,3,5,6,9,12Vitamin C Option E: Vitamins A, D, E, K The correct answer is Option D.
Explanation A Water soluble vitamins are B1, B2, B3, B5, B6, B9 and B12. They are not stored in the body and must be consumed regularly. Fat soluble vitamins are A, D, E and K. They are stored in the body and can be toxic in high doses.
Explanation B The correct answer is D! Vitamins B1,2,3,5,6,9,12 and Vitamin C are all water soluble. Vitamins A, D, E and K are all fat soluble.
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Question 11
The enzyme phosphofructokinase 1 catalyzes the conversion of fructose 6 phosphate to fructose 1 , 6 bisphosphate during glycolysis .Which of the following up regulates this enzyme in most cells ? Option A: ATP Option B: AMP Option C: lactic acid Option D: fructose 2 ,6 bisphosphate Option E: fructose 1 ,6 bisphosphate The correct answer is Option B.
Explanation A Phosphofructokinase 1 is the rate limiting step in glycolysis. It is inhibited by ATP and citrate and activated by AMP and fructose 2 ,6 bisphosphate.
Explanation B ATP is an allosteric inhibitor of phosphofructokinase 1. This is because ATP is a product of glycolysis and high levels of ATP indicate that the cell has sufficient energy and therefore does not need to proceed with glycolysis. AMP is an allosteric activator of phosphofructokinase 1. This is because AMP is a product of ATP hydrolysis and high levels of AMP indicate that the cell has low energy and therefore needs to proceed with glycolysis. Fructose 2 ,6 bisphosphate is an allosteric activator of phosphofructokinase 1. This is because fructose 2 ,6 bisphosphate is a product of the phosphofructokinase 2/fructose 2 ,6 bisphosphatase bifunctional enzyme. This enzyme is regulated by glucagon and insulin. When glucagon is present, it activates the phosphofructokinase 2/fructose 2 ,6 bisphosphatase bifunctional enzyme. This enzyme converts fructose 6 phosphate to fructose 2 ,6 bisphosphate. When insulin is present, it inactivates the phosphofructokinase 2/fructose 2 ,6 bisphosphatase bifunctional enzyme. This enzyme converts fructose 2 ,6 bisphosphate to fructose 6 phosphate.
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Question 12
A patient presents to A&E with a severely injured leg. His friend tells you that he had a high impact fall following a bullet being shot into the back of his leg, which he believes is still inside. You would like to have some imaging of his leg done to determine the appropriate management for this patient, as you want to better determine the trauma to his bones, and the surrounding soft tissue. You would like to minimise the amount of radiation for this patient, as he recently had a CT of his abdomen for suspected small bowel obstruction, which you know has approximately 3 years of background radiation associated with this scan. What imaging would you want to do? Option A: X-Ray Option B: MRI Option C: DEXA Scan Option D: CT The correct answer is Option A.
Explanation A X-rays are the best option as they are the least invasive and involve the lowest dose of radiation. While MRI is excellent for soft tissue, it is not as good as CT for bone trauma. DEXA scans are used to measure bone density and are not useful in this situation. CT scans are excellent for bone trauma, but involve a much higher dose of radiation than X-rays.
Explanation B X-rays are the best option as they are the least invasive and have the lowest radiation dose. MRI is the best option for soft tissue imaging, but it is not as good for bone trauma as X-rays. DEXA scans are used to measure bone density and are not suitable for this patient. CT scans are good for bone trauma, but they have a higher radiation dose than X-rays.
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Question 13
Which of the following statements regarding bisoprolol is correct? Option A: It is indicated for bradycardia Option B: It is commonly prescribed amongst asthmatics Option C: It prevents phospholamban from inhibiting SERCA Option D: It is an antagonist of β1 receptors Option E: It increases lusitropy The correct answer is Option D.
Explanation A A - Incorrect, it is contraindicated in bradycardiaB - Incorrect, it is contraindicated in asthmaticsC - Incorrect, this is the mechanism of action of digoxinD - Correct, it is a selective β1 receptor antagonistE - Incorrect, it decreases lusitropy
Explanation B Bisoprolol is a selective β1 adrenoceptor antagonist. It is used to treat hypertension, heart failure and angina. It is not indicated for bradycardia as it can worsen the condition. It is not commonly prescribed amongst asthmatics as it is selective for β1 receptors and does not affect β2 receptors which are involved in bronchodilation. It prevents phospholamban from inhibiting SERCA by increasing the amount of cAMP in the cell. It decreases lusitropy by decreasing the amount of calcium available for binding to troponin C.
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Question 14
Pip is sat eating her roast dinner and thinks about how food moves down her oesophagus. She remembers that the epiglottis prevents food from going into her trachea. She wonders what sort of cartilage it is made out of, to allow this movement to happen. Can you help her? Option A: It is made out of hyaline cartilage Option B: Made out of fibrocartilage Option C: Made out of elastic cartilage Option D: Loose areolar Option E: Dense irregular The correct answer is Option C.
Explanation A The correct answer is C! The epiglottis is made out of elastic cartilage. This is because it needs to be flexible to move up and down to allow food to pass into the oesophagus. Hyaline cartilage is found in the trachea and larynx, fibrocartilage is found in the intervertebral discs and menisci of the knee, and dense irregular connective tissue is found in the dermis of the skin.
Explanation B The epiglottis is made out of elastic cartilage. This is because it needs to be flexible to move up and down to allow food to pass into the oesophagus. Hyaline cartilage is found in the trachea and larynx where it needs to be rigid to keep the airways open. Fibrocartilage is found in the intervertebral discs and menisci of the knee where it needs to be strong and able to withstand pressure.
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Question 15
What one food source below has the best glycaemic index? (best meaning, which food gives more of a sustained energy) Option A: Apple (GI of 38) Option B: Cornflour (GI of 70) Option C: New potatoes (boiled) (GI of 63) Option D: Spinach (GI of 15) Option E: Jelly Beans (GI of 80) The correct answer is Option D.
Explanation A The glycaemic index is a measure of how much a food increases blood glucose levels. A higher GI means that the food increases blood glucose levels more quickly and for a longer period.
Explanation B The glycaemic index is a measure of how quickly a food causes a rise in blood glucose levels. Foods with a high GI cause a rapid rise in blood glucose levels, which is followed by a rapid drop. This can lead to a feeling of tiredness and hunger shortly after eating. Foods with a low GI cause a slower, more sustained rise in blood glucose levels. This is because they are digested more slowly. The lower the GI, the better the food is for sustained energy.
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Question 16
Charlotte, a 45 year old asthmatic presents to hospital after blacking out at work. She says she has been feeling very unwell for the last few days, struggling to catch her breath – she has been using her inhalers but they haven’t helped very much. She was recently in a car accident and has been on strong painkillers to manage the pain. She admits that she smokes 10 a day.You take her arterial blood gases and the results are as follows:pH: 7.26 (7.35-7.45 normal)PaCO2 : 8.8 kPa (4.5- 6 normal)PaO2: 7.7 kPa (11 to 14 normal)BE: -3.5 (normal -2 to 2 )HCO3-: 22 mmol/L (22- 28 normal)Sats : 94% (>96 normal) What best describes her current condition? Option A: Metabolic acidosis with compensation Option B: Respiratory acidosis with no compensation Option C: Metabolic acidosis with no compensation Option D: Respiratory alkalosis with compensation Option E: Respiratory acidosis with compensation The correct answer is Option B.
Explanation A The patient is hypoventilating due to her asthma and COPD. This has led to a rise in CO2, causing respiratory acidosis. The low pH is due to the high CO2 levels. The low PaO2 is due to the hypoventilation and her asthma. The BE is low due to the respiratory acidosis. The HCO3- is normal, meaning there is no metabolic compensation.
Explanation B The pH is low, so it is an acidosis. The PaCO2 is high, so it is a respiratory acidosis. The HCO3- is normal, so there is no compensation.
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Question 17
Which ion is released in the post-synaptic membrane during an IPSP? Option A: Chloride ion Option B: Potassium ion Option C: Sodium ion Option D: Calcium ion Option E: Magnesium ion The correct answer is Option A.
Explanation A An IPSP is caused by an influx of chloride ions (Cl-) which hyperpolarises the membrane. This is because the equilibrium potential for chloride is more negative than the resting membrane potential. This makes the membrane more negative and therefore less likely to fire an action potential.
Explanation B A is correct! An IPSP is a hyperpolarisation of the post-synaptic membrane. This is caused by the opening of chloride channels. This makes the membrane potential more negative, making it less likely that an action potential will be generated.
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Question 18
You working in A and E and treat a 12 year old boy who has an injury to his ankle. He says that he sustained the injury when he tripped over and fell in the night. After further questioning he also reveals that he is often very tired and weak, has problems with his vision, and is worried as he is much smaller than the other children in his class. You are concerned that he may have a dietary deficiency, and so run some tests that confirm your suspicions. Based on the boy's symptoms, what could he be deficient in? Option A: Vitamin A. Option B: Vitamin B3. Option C: Vitamin B12. Option D: Vitamin C. Option E: Essential amino acids. The correct answer is Option A.
Explanation A Vitamin A deficiency can cause all of the symptoms described. Vitamin A is important for vision, immune function, and growth. Vitamin B3 deficiency can cause a rash, diarrhoea, and confusion. Vitamin B12 deficiency can cause fatigue, weakness, and problems with vision. Vitamin C deficiency can cause fatigue, weakness, and bleeding gums. Essential amino acids are important for growth and development.
Explanation B The boy's symptoms are all signs of Vitamin A deficiency. Vitamin A is important for vision, and deficiency can cause night blindness. It is also important for growth and development, and deficiency can cause growth retardation. Vitamin A is found in liver, fish, eggs and dairy products. Vitamin A deficiency is common in children in developing countries where they are often given vitamin A supplements.
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Question 19
When blood glucose and insulin levels are low, glucagon is secreted from alpha cells in the pancreas. Using a cell signalling pathway, protein kinase A is activated. What effect does protein kinase A have on glycogen phosphorylase and glycogen synthase and how does this alter their activity? Option A: Switches glycogen phosphorylase off- decreases glycogenolysis Switches glycogen synthase on- increases glycogen synthesis Option B: Switches glycogen phosphorylase on- increases glycogenolysis Switches glycogen synthase off- decreases glycogen synthesis Option C: Switches glycogen phosphorylase on- decreases glycogenolysisSwitches glycogen synthase off- increases glycogen synthesis Option D: Switches glycogen phosphorylase off- increases glycogenolysisSwitches glycogen synthase on- decreases glycogen synthesis The correct answer is Option B.
Explanation A B is the correct answer! When blood glucose and insulin levels are low, glucagon is secreted from alpha cells in the pancreas. Using a cell signalling pathway, protein kinase A is activated. What effect does protein kinase A have on glycogen phosphorylase and glycogen synthase and how does this alter their activity? Protein kinase A switches glycogen phosphorylase on- increases glycogenolysisProtein kinase A switches glycogen synthase off- decreases glycogen synthesis
Explanation B Glucagon activates protein kinase A which phosphorylates glycogen phosphorylase to switch it on. This increases glycogenolysis (breakdown of glycogen). Protein kinase A also phosphorylates glycogen synthase to switch it off. This decreases glycogen synthesis.
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Question 20
A 28 year old male patient weighing 72kg undergoes minor surgery on his leg and requires an injection of 0.5% lidocaine as a local anaesthetic. The doctor gives him an initial dose of 10mL. The maximum does is 2.65mg/kg. To 1 decimal place how much more lidocaine can be administered? Option A: 190.8mL Option B: 28.2mL Option C: 50mL Option D: 0.5mL Option E: 140.8mL The correct answer is Option B.
Explanation A 0.5% lidocaine = 5mg in 100mL. 10mL = 5mg. Max dose = 2.65mg/kg. 72kg = 191.2mg. 191.2mg - 5mg = 186.2mg. 186.2mg = 186.2/5 x 100mL = 3724mL. 3724mL - 10mL = 3714mL. Wait, this is not in mL. 0.5% lidocaine = 5mg in 100mL. 10mL = 5mg. Max dose = 2.65mg/kg. 72kg = 191.2mg. 191.2mg - 5mg = 186.2mg. 186.2mg = 186.2/5 x 100mL = 3724mL. Wait, this is not in mL. 0.5% lidocaine = 5mg in 100mL. 10mL = 5mg. Max dose = 2.65mg/kg. 72kg = 191.2mg. 191.2mg -
Explanation B 0.5% lidocaine is 5mg per 10mL. The maximum dose is 2.65mg/kg. So the maximum dose is 2.65 x 72 = 190.8mg. 190.8mg / 5mg = 38.16mL. He has already had 10mL so 38.16 - 10 = 28.16mL. Rounded to 1 decimal place this is 28.2mL.
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Question 21
A man presents to A&E with a suspected stroke. You attempt to speak with him, and despite his sentences being fluent, the words he is speaking are confused and don't appear to make much sense. What artery has been most likely occluded? Option A: Right middle cerebral artery Option B: Right anterior cerebral artery Option C: Left anterior cerebral artery Option D: Left middle cerebral artery Option E: Both right and left middle cerebral arteries The correct answer is Option D.
Explanation A The correct answer is D - the left middle cerebral artery. The middle cerebral artery supplies the lateral surface of the frontal, parietal and temporal lobes. The left middle cerebral artery is responsible for the production of speech. The symptoms described are known as Wernicke's aphasia.
Explanation B The patient is experiencing expressive aphasia, which is the inability to produce language. This is caused by damage to Broca's area, which is located in the left frontal lobe. The left middle cerebral artery supplies Broca's area. Therefore, occlusion of the left middle cerebral artery is the most likely cause of the patient's symptoms.
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Question 22
A mother takes her child to the GP as he is below average in height for a boy his age. After taking some tests the boy is found to be lacking in a hormone. What is the hormone likely to be? Option A: Cortisol Option B: Thyroxine Option C: Insulin The correct answer is Option B.
Explanation A Thyroxine is a hormone that is essential for growth and development. A deficiency in thyroxine can lead to growth retardation and a lack of development. Cortisol is a steroid hormone that is essential for growth and development. A deficiency in cortisol can lead to growth retardation and a lack of development. Insulin is a hormone that is essential for growth and development. A deficiency in insulin can lead to growth retardation and a lack of development.
Explanation B Thyroxine is a hormone that is produced by the thyroid gland and is important for growth and development. A lack of thyroxine can cause a condition called cretinism which is a form of intellectual disability.
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Question 23
Ellie presents to the doctor at 14 weeks pregnant. She was not planning to fall pregnant and is slightly worried that she has not been aware of her pregnancy up until now.You run some blood tests, and find that her mean cell volume (MCV) is at 120fl (normal is up to 105fl in pregnancy). This, in conjunction with some other tests, suggests that she has a certain type of anaemia.With this in mind, what are you most worried about for the newborn? Option A: Thrombocytopenia Option B: Mechanical problems during labour Option C: Haemolytic disease of the newborn Option D: Neural tube defect Option E: You are not concerned about any problems The correct answer is Option D.
Explanation A The MCV is elevated, which suggests that the anaemia is macrocytic. This is most likely due to folate deficiency. Folate is essential for the synthesis of DNA and RNA, and is required for the formation of neural tubes. If there is a deficiency, the baby is at risk of having a neural tube defect.
Explanation B The MCV is a measure of the average size of red blood cells. A high MCV suggests that the red blood cells are larger than normal, which is known as macrocytic anaemia. This is most commonly caused by a deficiency of folate or vitamin B12. Folate and B12 are both essential for the formation of DNA. If there is a deficiency of either of these vitamins, the DNA of the red blood cells cannot be properly replicated, and the cells cannot divide properly. This results in the production of large, immature red blood cells. Folate and B12 are both essential for the formation of DNA. If there is a deficiency of either of these vitamins, the DNA of the red blood cells cannot be properly replicated, and the cells cannot divide properly. This results in the production of large, immature red blood cells. Folate and B12 are both essential for the formation of DNA. If there is a deficiency of either of these vitamins, the DNA of the red blood cells cannot be properly replicated, and the cells cannot divide properly. This results in the production of large, immature red blood cells. Folate and B12 are both essential for the formation of DNA. If there is a deficiency of either of these vitamins, the DNA of the red blood cells cannot be properly replicated, and the cells cannot divide properly. This results in the production of large, immature red blood cells. Folate and B12 are both essential for the formation of
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Question 24
I'm in the library when I log onto peerwise to find out I've got the highest number of followers, shamefully my corpus cavernosum fills up with blood due to the 1. I quickly grab my coat to place on my lap when I bang my quadriceps tendon on the desk, its collagen is 2 in nature. Immediately after this I cry out in pain, some mucoid saliva from my sublingual gland innervated by 3 travels from my mouth onto my notes. The mucoid saliva is now covering my notes, specifically the sentence: "the baroreceptors in the carotid sinus is innervated by 4". After staring at my saliva for a while I start to think about different types of sputum, in particular green sputum whose colour is caused by the enzyme 5. I decide to poke my saliva in order to trigger my 6 memory to remember all these answers. What does 1,2,3,4,5 and 6 stand for? Every answer corresponds to a different case. Option A: Sympathetic nervous systemViscoelasticGlossopharyngeal nerveVagus nerveMyeloperoxidaseHaptic Option B: Parasympathetic nervous systemViscoelasticFacial nerveGlossopharyngeal nerveMatrix metalloproteinaseIconic Option C: Parasympathetic nervous systemViscoelasticFacial nerveGlossopharyngeal nerveMyeloperoxidaseHaptic Option D: Parasympathetic nervous systemElasticFacial nerveVagus nerveMatrix metalloproteinaseIconic Option E: Parasympathetic nervous systemViscoelasticGlossopharyngeal nerveGlossopharyngeal nerveMyeloperoxidaseHaptic The correct answer is Option C.
Explanation A 1. Corpus cavernosum is part of the penis and is made of smooth muscle, which is viscoelastic. The sympathetic nervous system causes smooth muscle to contract, so the parasympathetic nervous system causes it to relax and fill with blood. 2. The quadriceps tendon is made of dense regular connective tissue, which is viscoelastic. 3. The sublingual gland is innervated by the facial nerve, which is a branch of the parasympathetic nervous system. 4. The baroreceptors in the carotid sinus are innervated by the glossopharyngeal nerve, which is a branch of the parasympathetic nervous system. 5. Green sputum is caused by the enzyme myeloperoxidase, which is released by neutrophils. Neutrophils are part of the innate immune system and are attracted to sites of infection by chemokines. They release myeloperoxidase, which contains iron and produces hydrogen peroxide, which is toxic to pathogens. 6. Haptic memory is the memory of the sense of touch.
Explanation B 1. Parasympathetic nervous system - the corpus cavernosum is innervated by the parasympathetic nervous system2. Viscoelastic - the quadriceps tendon is made of viscoelastic collagen3. Facial nerve - the sublingual gland is innervated by the facial nerve4. Glossopharyngeal nerve - the baroreceptors in the carotid sinus are innervated by the glossopharyngeal nerve5. Myeloperoxidase - the green colour of sputum is caused by the enzyme myeloperoxidase6. Haptic - the haptic memory is the memory of touch
Which explanation reasons better for the correct answer?