-
Question 1
Correct
-
Glucose absorption in the small intestine is coupled with which of the following electrolytes?
Your Answer: Na
Explanation:Sodium-glucose linked transporter are family of proteins of different types. SGLT1 transporter is found in the intestinal mucosa of the small intestine and absorbs glucose via cotransport of Na+ ions.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 2
Correct
-
The end product of trehalase action on oligosaccharides is
Your Answer: Two glucose molecules
Explanation:Disaccharides are glycoside hydrolases, enzymes that break down certain types of sugars called disaccharides into simpler sugars called monosaccharides.Examples of disaccharides:Lactase (breaks down lactose into glucose and galactose)Maltase (breaks down maltose into 2 glucoses)Sucrase (breaks down sucrose into glucose and fructose)Trehalase (breaks down trehalose into 2 glucoses)
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 3
Correct
-
Selectins
Your Answer: Interact with carbohydrate ligands or mucin complexes on leucocytes and endothelial cells
Explanation:Selectins are involved in constitutive lymphocyte homing, and in chronic and acute inflammation processes, including post-ischemic inflammation. Each selectin has a carbohydrate recognition domain that mediates binding to specific glycans on apposing cells.
-
This question is part of the following fields:
- Cell Biology
- Medicine
-
-
Question 4
Incorrect
-
Which of the following statements is most suitable to describe necrosis?
Your Answer: Energy (ATP) dependant.
Correct Answer: Significant inflammatory response
Explanation:Necrosis is the death of most or all of the cells in an organ or tissue due to disease, injury, or failure of the blood supply. Cellular death due to necrosis does not follow the (regulated) apoptotic signal transduction pathway, but rather various receptors are activated, and result in the loss of cell membrane integrity and an uncontrolled release of products of cell death into the extracellular space. This initiates in the surrounding tissue an inflammatory response which attracts leukocytes and nearby phagocytes which eliminate the dead cells by phagocytosis.
-
This question is part of the following fields:
- Cell Biology
- Medicine
-
-
Question 5
Correct
-
The neurotransmitter utilised by the Purkinje cells is:
Your Answer: GABA
Explanation:The cerebellar cortex consist of 3 layers: the molecular layer, the granular cell layer and the Purkinje cell layer. Purkinje cells play a fundamental role in controlling motor movement. They release a neurotransmitter called GABA (gamma-aminobutyric acid) which exerts inhibitory actions thereby reducing transmission of impulses. These inhibitory functions enable purkinje cells to regulate and coordinate motor movements.
-
This question is part of the following fields:
- Medicine
- Neurology
-
-
Question 6
Incorrect
-
Under normal conditions (where n represents the number of chromosome pairs), just before mitosis begins, how many chromosomes are contained in the nucleus of each somatic cell:
Your Answer: 1n
Correct Answer: 4n
Explanation:In a normal somatic cell there are 2n chromosome but in a replicating cell just before mitosis the chromosomes duplicate but are still joined via the centrosome. Thus there are 4n chromosomes. After completion of mitosis the number goes back to 2n.
-
This question is part of the following fields:
- Genetics
- Medicine
-
-
Question 7
Correct
-
Question 8
Incorrect
-
A 22-year-old university student is admitted after taking drugs at a night club. Which of the following features suggest she had taken ecstasy (MDMA)?
Your Answer: Metabolic acidosis
Correct Answer: A pyrexia of 40Ā°C
Explanation:MDMA commonly known as ecstasy or molly, is a psychoactive drug primarily used as a recreational drug. The desired effects include altered sensations, increased energy, empathy, and pleasure. Features of MDMA abuse include hyponatraemia, tachycardia, hyperventilation, and hyperthermia.
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 9
Correct
-
Which of the following initiates migrating motor complex
Your Answer: Motilin
Explanation:Migrating motor complexes (MMC) are thought to be partially regulated by motilin, which is initiated in the stomach as a response to vagal stimulation, and does not directly depend on extrinsic nerves.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 10
Incorrect
-
The inverse stretch reflex causing muscle relaxation when excessive force is applied to a muscle is mediated by which sensory organ?
Your Answer: Muscle spindle
Correct Answer: Golgi tendon organ
Explanation:Both the muscle spindle and Golgi tendon body are proprioceptors. The Golgi tendon reflex is a normal component of the reflex arc of the peripheral nervous system. In a Golgi tendon reflex, skeletal muscle contraction causes the antagonist muscle to simultaneously lengthen and relax. This reflex is also called the inverse myotatic reflex, because it is the inverse of the stretch reflex.
-
This question is part of the following fields:
- Medicine
- Neurology
-
-
Question 11
Correct
-
Absorption of fructose is via:
Your Answer: Facilitated diffusion
Explanation:Dietary fructose may be ingested as a monosaccharide or as a disaccharide. Sucrose is hydrolysed by sucrase to produce equal amounts of glucose and fructose and in this form, is usually completely absorbed. Fructose is mostly absorbed in the small intestine through GLUT-5 transporter mediated facilitative diffusion. This is an energy independent process.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 12
Correct
-
Peristalsis is an example of:
Your Answer: Enteric nervous system
Explanation:Peristalsis is a type of contraction where radial symmetrical contraction and relaxation of muscles propagates food in a downward wave through the gut. The enteric nervous system is one of the main divisions of the nervous system and consists of a mesh-like system of neurons that controls the function of the gastrointestinal tract. It has an independent reflex activity. The neurons of this system re collected into two types of ganglia: myenteric (or Auerbach’s) and submucosal (or Meissner’s plexuses). Myenteric plexuses are located between the inner and outer layers of the muscularis externa, while submucosal plexuses are located in the submucosa.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 13
Incorrect
-
A 35-year-old male presented to the ER after being rescued from a house fire. He complained of feeling dizzy and having a worsening headache. On examination, he was dyspnoeic, drowsy and confused. There was no evidence of facial burns and no stridor. He was normotensive, tachycardic (pulse rate: 102 bpm), tachypnoeic (respiratory rate: 35/min) and had O2 saturation of 100% in room air. His venous blood gas results are given below: pH - 7.28pCO2 - 3.5 kPapO2 - 15.9 kPaNa+ - 139 mmol/LK+ - 4.5 mmol/LBicarbonate - 11 mmol/LChloride - 113 mmol/LLactate - 13.6 mmol/LKeeping in mind the likely diagnosis, which among the following is the most appropriate intervention for this patient?
Your Answer: Intubate and ventilate
Correct Answer: Intravenous hydroxocobalamin
Explanation:The most appropriate intervention in this patient is intravenous hydroxocobalamin.The clinical scenario provided is suggestive of acute cyanide toxicity secondary to burning plastics in the house fire. Cyanide ions inhibit mitochondrial cytochrome oxidase, preventing aerobic respiration. This manifests in normal oxygen saturations, a high pO2 and flushing (or ‘brick red’ skin) brought on by the excess oxygenation of venous blood. In the question above it is important to note that the blood gas sample given is venous rather than arterial. His blood gas also demonstrates an increased anion gap, consistent with his high lactate (generated by anaerobic respiration due to the inability to use available oxygen).The recommended treatment for moderate cyanide toxicity in the UK is one of three options: sodium thiosulfate, hydroxocobalamin or dicobalt edetate. Among the options given is hydroxocobalamin and this is, therefore, the correct answer. Hydroxocobalamin additionally has the best side-effect profile and speed of onset compared with other treatments for cyanide poisoning.Other options:- Intubation would be appropriate treatment in the context of airway burns but this patient has no evidence of these, although close monitoring would be advised. – High-flow oxygen is the treatment for carbon monoxide poisoning – a sensible differential, but this man’s very high lactate and high venous pO2 fit better with cyanide toxicity. Intravenous dexamethasone would be another treatment for airway oedema once an endotracheal tube had been placed. – Intravenous sodium nitroprusside is a treatment for high blood pressure that can cause cyanide poisoning, and would, therefore, be inappropriate.Note:Cyanide may be used in insecticides, photograph development and the production of certain metals. Toxicity results from reversible inhibition of cellular oxidizing enzymesClinical presentation:Classical features: brick-red skin, the smell of bitter almondsAcute: hypoxia, hypotension, headache, confusionChronic: ataxia, peripheral neuropathy, dermatitisManagement:Supportive measures: 100% oxygenDefinitive: hydroxocobalamin (intravenously), also a combination of amyl nitrite (inhaled), sodium nitrite (intravenously), and sodium thiosulfate (intravenously).
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 14
Correct
-
Question 15
Incorrect
-
Select the correct statement regarding portal hypertension.
Your Answer: Portal blood flow through the liver is increased.
Correct Answer: The total vascular resistance of the hepatic sinusoids is increased.
Explanation:Portal hypertension is increased blood pressure within the portal venous system. This happens mainly due to liver damage which increases the vascular resistance of hepatic sinusoids by interfering with the normal blood flow. Portal blood pressure increases and flow through the liver decreases. Normal portal venous pressure is between 5-10 mmHg and in portal hypertension itās usually more than 10 mmHg. This high pressure can cause accumulation of fluid in the peritoneal cavity known as ascites. To overcome the pressure, the portal vein starts to drain blood to systemic circulation via porto-systemic shunts. The connection between the portal vein and inferior vena cava is known as the porto caval shunt. Due to damaged hepatocytes, detoxification of substances absorbed in the intestine is impaired and the former shunt mixes non-detoxified blood with the systemic circulation. These toxic substances may affect neurons causing hepatic encephalopathy which is a major complication of portal hypertension.
-
This question is part of the following fields:
- Hepatobiliary
- Medicine
-
-
Question 16
Incorrect
-
A 51-year-old real estate agent takes hydrocortisone 20mg in the mornings and 5mg at night for Addisonās disease. The endocrinology consultant would like her to take prednisolone instead. What dose of prednisolone should be started?
Your Answer: 25 mg
Correct Answer: 7 mg
Explanation:1mg Prednisolone = 4mg hydrocortisone, so the actual equivalent daily dose is 7mg.
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 17
Incorrect
-
Which one of the following is able to move across cell membranes by passive diffusion?
Your Answer: Na+
Correct Answer: CO2
Explanation:The cell membrane is permeable to water molecules and a few other small, uncharged, molecules like oxygen (O2) and carbon dioxide (CO2). Larger molecules like glucose or charged ions are unable to cross passively.
-
This question is part of the following fields:
- Cell Biology
- Medicine
-
-
Question 18
Incorrect
-
Complement system help dispose waste products after which natural process?
Your Answer: Infection
Correct Answer: Apoptosis
Explanation:The complement system is a part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism or apoptosis. It is part of the innate immune system.
-
This question is part of the following fields:
- Immunology
- Medicine
-
-
Question 19
Correct
-
The coronary arteries fill during?
Your Answer: Diastole
Explanation:During systole the coronary arteries collapse as a result of the pressure due to contraction that is exerted on them. During diastole the heart muscle relaxes and the pressure on the coronary vessels is relieved allowing blood to flow through them to the subendocardium.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 20
Correct
-
Which one of these features is typical of dermatomyositis?
Your Answer: Gottron's papules over knuckles of fingers
Explanation:Dermatomyositis is a long-term inflammatory disorder which affects muscles. Its symptoms are generally a skin rash and worsening muscle weakness in the proximal muscles (for example, the shoulders and thighs) over time. These may occur suddenly or develop over months. Other symptoms may include weight loss, fever, lung inflammation, or light sensitivity. Complications may include calcium deposits in muscles or skin.The skin rash may manifest as aheliotrope (a purplish color) or lilac, but may also be red. It can occur around the eyes along with swelling, as well as the upper chest or back ( shawl sign) or V-sign above the breasts and may also occur on the face, upper arms, thighs, or hands. Another form the rash takes is called Gottron’s sign which are red or violet, sometimes scaly, slightly raised papules that erupt on any of the finger joints (the metacarpophalangeal joints or the interphalangeal joints)
-
This question is part of the following fields:
- Dermatology
- Medicine
-
-
Question 21
Correct
-
The conversion of fructose to fructose 1-phosphate is catalysed by:
Your Answer: Fructokinase
Explanation:The first step in the metabolism of fructose is the phosphorylation of fructose to fructose 1-phosphate by fructokinase.
-
This question is part of the following fields:
- Medicine
- Metabolism
-
-
Question 22
Correct
-
Question 23
Incorrect
-
The complex twisting and folding of peptide chains describes which order of protein structure?
Your Answer: Quaternary structure
Correct Answer: Secondary structure
Explanation:Secondary Structure refers to the coiling or folding of a polypeptide chain that gives the protein its 3-D shape. There are two types of secondary structures: the alpha (Ī±) helix and the beta (Ī²) pleated sheet.
-
This question is part of the following fields:
- Medicine
- Metabolism
-
-
Question 24
Correct
-
Regarding DNA cloning and sequencing, all of the following are true, except:
Your Answer: Yeast artificial chromosomes ( yacs) are vectors
Explanation:Yeast chromosomes cannot be used as a vector. All the rest are true. Vectors can be bacteria, viruses and plasmids. DNA ligase binds the DNA fragment to the host DNA after insertion. Fluorescence can be used to visualize them.
-
This question is part of the following fields:
- Genetics
- Medicine
-
-
Question 25
Correct
-
What is the most appropriate management of a DVT during pregnancy?
Your Answer: Heparin
Explanation:Low molecular weight heparin (LMWH) is safe in pregnancy and is therefore the first line management. Warfarin is teratogenic and must be avoided whilst the other options have no role to play.
-
This question is part of the following fields:
- Medicine
- Respiratory
-
-
Question 26
Incorrect
-
In the functional unit of the liver (acinus), the oxygenationā¦
Your Answer: Reduces towards the periphery
Correct Answer: Reduces towards the centre
Explanation:Cells located close to the portal triad or peripheral zone which consist of arterioles from the hepatic artery are the most oxygenated cells. Cells in the central zone are least oxygenated and mainly receive blood supply from the central vein which is a branch of the hepatic vein.
-
This question is part of the following fields:
- Hepatobiliary
- Medicine
-
-
Question 27
Correct
-
Using the Cockcroft-Gault formula, what will the estimated creatinine clearance be of a 55 year old male who weighs 75kg and has a serum creatinine of 150mg/dL?
Your Answer: 0.59ml/min
Explanation:A commonly used surrogate marker for estimate of creatinine clearance is the Cockcroft-Gault (CG) formula, which in turn estimates GFR in ml/min:CCr = [(140-age) x Mass(kg)]/[72 x serum creatinine (mg/dL)](multiply by 0.85 for women)Therefore CCr = (85 x 75)/(72 x 150) = 0.59
-
This question is part of the following fields:
- Medicine
- Renal
-
-
Question 28
Correct
-
Question 29
Correct
-
Erythropoietin is synthesized by which cells of the nephron?
Your Answer: Tubular interstitial cells
Explanation:Erythropoietin is produced by interstitial fibroblasts in the kidney in close association with peritubular capillary and proximal convoluted tubule. It is also produced in perisinusoidal cells in the liver. While liver production predominates in the fetal and perinatal period, renal production is predominant during adulthood.
-
This question is part of the following fields:
- Medicine
- Renal
-
-
Question 30
Correct
-
There will be a proportion of people in a population who have the given condition, disease or attribute at a specified point in time or over a specified period of time. Which of following is the best term which can describe the above?
Your Answer: Prevalence
Explanation:Prevalence refers to the total number of cases of a particular disease or condition present in a population at a specific point in time or over a specified period. It provides a measure of how widespread the disease or condition is within the population.
Specificity and sensitivity are terms used to describe the accuracy of diagnostic tests.
Probability refers to the likelihood of an event occurring.
Incidence isĀ a measure of how commonly or frequently a disease occurs in a specified population over a period by providing a quick measurement of new diseaseĀ diagnoses.
-
This question is part of the following fields:
- Medicine
- Research Skills
-
SESSION STATS - PERFORMANCE PER SPECIALTY
