-
Question 1
Incorrect
-
Which of the following immunoglobulins is most important for mast cell degranulation:
Your Answer: IgG
Correct Answer: IgE
Explanation:IgA is the major Ig in secretions, particularly from the gastrointestinal tract (but also in saliva, tears, sweat and breast milk).IgE is important for mast cell degranulation in allergic and antiparasitic response. In the allergic response, the plasma cell produces IgE-antibodies, which, like antibodies of other immunoglobulin isotypes, are capable of binding a specific allergen via its Fab portion.IgG is the most abundant in plasma (comprising 80% of normal serum immunoglobulin) and the main circulatory Ig for the secondary immune response.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 2
Incorrect
-
A 27-year-old man has been diagnosed with testicular cancer and has spread to the regional lymph nodes. The lymph from the testes will drain to which of the following nodes?
Your Answer: Deep inguinal lymph nodes
Correct Answer: Para-aortic lymph nodes
Explanation:Testes are retroperitoneal organs and its lymphatic drainage is to the lumbar and para-aortic nodes along the lumbar vertebrae.The scrotum is the one which drains into the nearby superficial inguinal nodes.The glans penis and clitoris drains into the deep inguinal lymph nodes.
-
This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
-
-
Question 3
Incorrect
-
Approximately what proportion of lymphocytes are B-cells:
Your Answer: 0.5
Correct Answer: 0.2
Explanation:B-cells (20% of lymphocytes) mature in the bone marrow and circulate in the peripheral blood until they undergo recognition of antigen. B-cell immunoglobulin molecules synthesised in the cell are exported and bound to the surface membrane to become the B-cell receptor (BCR) which can recognise and bind to a specific antigen (either free or presented by APCs). The BCR is also important for antigen internalisation, processing and presentation to T helper cells. Most antibody responses require help from antigen-specific T helper cells (although some antigens such as polysaccharide can lead to T-cell independent B-cell antibody production). When the B-cell is activated, the receptor itself is secreted as free soluble immunoglobulin and the B-cell matures into a memory B-cell or a plasma cell (a B-cell in its high-rate immunoglobulin secreting state). Plasma cells are non-motile and are found predominantly in the bone marrow or spleen. Most plasma cells are short-lived (1 – 2 weeks) but some may survive much longer. A proportion of B-cells persist as memory cells, whose increased number and rapid response underlies the augmented secondary response of the adaptive immune system.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 4
Incorrect
-
Atracurium is used as a muscle relaxant during endotracheal intubation. This drug’s mechanism of action is best described by which of the following?
Your Answer: Acetylcholinesterase inhibitor
Correct Answer: Nicotinic acetylcholine receptor antagonist
Explanation:Atracurium is a non-depolarizing neuromuscular blocker that is used to help with intubation and controlled ventilation by causing muscle relaxation and paralysis. At the neuromuscular junction’s post-synaptic membrane, atracurium competes with acetylcholine for nicotinic (N2) receptor binding sites. This prevents the receptors from being stimulated by acetylcholine. Muscle paralysis occurs gradually due to the competitive blockade.
-
This question is part of the following fields:
- Anaesthesia
- Pharmacology
-
-
Question 5
Incorrect
-
The following are all examples of type III hypersensitivity EXCEPT for:
Your Answer: Systemic lupus erythematosus
Correct Answer: Goodpasture's syndrome
Explanation:Examples of type III reactions include:Extrinsic allergic alveolitisSystemic lupus erythematosus (SLE)Post-streptococcal glomerulonephritisReactive arthritisRheumatoid arthritis
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 6
Incorrect
-
A 60-year-old patient with a history of hypertension and chronic kidney disease (CKD) walks into the clinic to discuss her most recent blood results indicating an accelerated progression of CKD.Which of the following is the correct definition for accelerated progression of CKD?
Your Answer: A sustained decrease in GFR of 15% or more within 12 months
Correct Answer: A sustained decrease in GFR of 15 ml/minute/1.73 m 2 per year
Explanation:Chronic kidney disease (CKD) is a disorder in which kidney function gradually deteriorates over time. It’s fairly prevalent, and it typically remains unnoticed for years, with only advanced stages of the disease being recognized. There is evidence that medication can slow or stop the progression of CKD, as well as lessen or prevent consequences and the risk of cardiovascular disease (CVD).CKD is defined as kidney damage (albuminuria) and/or impaired renal function (GFR 60 ml/minute per 1.73 m2) for three months or longer, regardless of clinical diagnosis.A prolonged decline in GFR of 25% or more with a change in GFR category within 12 months, or a sustained drop in GFR of 15 ml/minute/1.73 m² per year, is considered accelerated CKD progression.End-stage renal disease (ESRD) is defined as severe irreversible kidney impairment with a GFR of less than 15 ml/minute per 1.73 m² and a GFR of less than 15 ml/minute per 1.73 m².
-
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 7
Incorrect
-
Diagnosis of HIV is predominantly made through which of the following:
Your Answer: Viral PCR
Correct Answer: Antibody detection
Explanation:Diagnosis of HIV is predominantly made through detection of HIV antibody and p24 antigen. Viral load (viral PCR) and CD4 count are used to monitor progression of disease.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 8
Correct
-
A 25-year old male is brought to the emergency room after a traffic accident. Upon examination, there was tenderness and erythema on the right acromioclavicular joint, with notable step deformity. On radiographic imaging, there is a superior elevation of the clavicle, a twice than normal coracoclavicular distance, and absence of fracture.Which of the following structure/s is/are likely to have ruptured?
Your Answer: Acromioclavicular ligament, coracoclavicular ligament and joint capsule
Explanation:Acromioclavicular joint injuries account for more than forty percent of all shoulder injuries. Mild injuries are not associated with any significant morbidity, but severe injuries can lead to significant loss of strength and function of the shoulder. Acromioclavicular injuries may be associated with a fractured clavicle, impingement syndromes, and more rarely neurovascular insults.The AC joint is a diarthrodial joint defined by the lateral process of the clavicle articulating with the acromion process as it projects anteriorly off the scapula. The joint is primarily stabilized by the acromioclavicular ligament, which is composed of an anterior, posterior, inferior, and superior component. Of note, the superior portion of the AC ligament is the most important component for the stability of the AC joint. Supporting structures include two coracoclavicular ligaments (trapezoid and conoid ligaments), which provide vertical stability, as well as the coracoacromial ligament.Patients with an AC joint injury typically present with anterosuperior shoulder pain and will describe a mechanism of injury of blunt trauma to the abducted shoulder or landing on an outstretched arm, suggestive of this type of injury. They may describe pain radiating to the neck or shoulder, which is often worse with movement or when they try to sleep on the affected shoulder. On examination, the clinician may observe swelling, bruising, or a deformity of the AC joint, depending on the degree of injury. The patient will be tender at that location. They may have a restriction in the active and passive range of motion secondary to pain. Piano key sign may be seen, with an elevation of the clavicle that rebounds after inferior compression.Standard X-rays are adequate to make a diagnosis of acromioclavicular joint injury and should be used to evaluate for other causes of traumatic shoulder pain.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 9
Correct
-
In the ventricular myocyte action potential, depolarisation occurs through the opening of:
Your Answer: Voltage-gated Na + channels
Explanation:An action potential (AP) is initiated when the myocyte is depolarised to a threshold potential of about -65 mV, as a result of transmission from an adjacent myocyte via gap junctions. Fast voltage-gated Na+channels are activated and a Na+influx depolarises the membrane rapidly to about +30 mV. This initial depolarisation is similar to that in nerve and skeletal muscle, and assists the transmission to the next myocyte.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 10
Incorrect
-
Metabolic hyperaemia harmonizes local blood flow with local O2 demand. If there is an increase in metabolic rate, the production of vasoactive metabolites increases. These metabolites act locally on the surrounding arterioles, causes vasodilation and an increase blood supply.Which of these metabolites is the most potent vasodilator in skeletal muscle?
Your Answer: CO 2
Correct Answer: K +
Explanation:Hyperaemia is the process where the body adjusts blood flow to meet the metabolic needs of different tissues in health and disease. Vasoactive mediators that take part in this process include K+, adenosine, CO2, H+, phosphates and H2O2. Although the mechanism is not clear, all these mediators likely contribute to some extent at different points.Specific organs are more sensitive to specific metabolites:K+ and adenosine are the most potent vasodilators in skeletal musclesCO2 and K+ are the most potent vasodilators in cerebral circulation.
-
This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
-
-
Question 11
Incorrect
-
A 23 year old student presents to ED with a widespread maculopapular rash. She recently had a sore throat and was started on a course of antibiotics. The most likely antibiotic that she was prescribed is:
Your Answer: Phenoxymethylpenicillin
Correct Answer: Amoxicillin
Explanation:Maculopapular rashes are commonly seen with ampicillin and amoxicillin. However they are not usually related to true penicillin allergy. Very often, they occur in patients with glandular fever and so, broad-spectrum penicillins should not be used blindly, for management and treatment of a sore throat. There is also an increased risk of rash in patients with acute or chronic lymphocytic leukaemia or in cytomegalovirus infection.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 12
Incorrect
-
A 30-year old male is brought to the emergency room after a terrible fall during a photoshoot. The patient reported falling on his right forearm. There is evident swelling and tenderness on the affected area, with notable weakness of the flexor pollicis longus muscle. Radiographic imaging showed a fracture on the midshaft of the right radius.Which of the following nerves is most likely injured in the case above?
Your Answer:
Correct Answer: The anterior interosseous nerve
Explanation:Flexor pollicis longus receives nervous supply from the anterior interosseous branch of median nerve, derived from spinal roots C7 and C8.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 13
Incorrect
-
Which of these immunoglobulin molecules can cross the placenta?
Your Answer:
Correct Answer: IgG
Explanation:An important mechanism that provides protection to the foetus is placental transfer of maternal IgG antibodies while his/her humoral response is inefficient. The only antibody class that significantly crosses the human placenta is IgG.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 14
Incorrect
-
Water is reabsorbed in which portion of the Henle loop:
Your Answer:
Correct Answer: Thin descending limb
Explanation:The loop of Henle consists of three functionally distinct segments: the thin descending segment, the thin ascending segment, and the thick ascending segment. About 20 percent of the filtered water is reabsorbed in the loop of Henle and almost all of this occurs in the thin descending limb. Na+ and Cl-ions are actively reabsorbed from the tubular fluid in the thick ascending limb via the Na+/K+/2Cl-symporter on the apical membrane. Because the thick ascending limb is water-impermeable, ion reabsorption lowers tubular fluid osmolality while raising interstitial fluid osmolality, resulting in an osmotic difference. Water moves passively out of the thin descending limb as the interstitial fluid osmolality rises, concentrating the tubular fluid. This concentrated fluid descends in the opposite direction of fluid returning from the deep medulla still higher osmolality areas.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 15
Incorrect
-
A patient is complaining of painless jaundice. His bilirubin levels are abnormally high.Which of the following statements about bile is correct?
Your Answer:
Correct Answer: Bile acids are amphipathic
Explanation:The liver produces bile on a constant basis, which is then stored and concentrated in the gallbladder. In a 24-hour period, around 400 to 800 mL of bile is generated.Bile is involved in the following processes:Fats are broken down into fatty acids.Waste products are eliminated.Cholesterol homeostasis is the balance of cholesterol in the body.The enteric hormones cholecystokinin and secretin are primarily responsible for bile secretion. When chyme from an unprocessed meal enters the small intestine, they are released, and they play the following function in bile secretion and flow:Cholecystokinin promotes gallbladder and common bile duct contractions, allowing bile to reach the intestine.Secretin enhances the secretion of bicarbonate and water by biliary duct cells, increasing the amount of bile and its flow into the gut.Bile acids have a hydrophobic and hydrophilic area, making them amphipathic. Bile acids’ amphipathic nature allows them to perform the following crucial functions:Emulsification of lipid aggregates increases the surface area of fat and makes it easier for lipases to digest it.Lipid solubilization and transport: solubilizes lipids by creating micelles, which are lipid clumps that float in water.
-
This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
-
-
Question 16
Incorrect
-
Insulin binds to the insulin receptor (IR) on cell surfaces to exert its action. The IR is a very specific transmembrane receptor belonging to the tyrosine kinase receptor class.One of these also activates the IR:
Your Answer:
Correct Answer: IGF-I
Explanation:Insulin receptor (IR), in addition to being activated by insulin, is also activated by IGF-I and IGF-II.The IR is a dimer with two identical subunits spanning the cell membrane and are connected by a single disulphide bond. The two sub-units include: The alpha chain situated on the exterior of the cell membrane and the beta chain spanning the cell membrane in a single segment. When insulin is detected, the alpha chains move together folding around the insulin making the beta chains move together, converting them into an active tyrosine kinase. This initiates a phosphorylation cascade increasing the expression of GLUT4 and allowing uptake of glucose by cells.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 17
Incorrect
-
Which of the following body location is the appropriate site to apply pressure when performing a carotid sinus massage?
Your Answer:
Correct Answer: Thyroid cartilage
Explanation:The common carotid artery runs through the neck and divides into internal and external carotid arteries on both sides near the upper thyroid cartilage. In emergency situations, carotid sinus massage is also used to diagnose or treat paroxysmal supraventricular tachycardia. During the procedure, to maximize access to the carotid artery, the patient is put in a supine position with the neck extended (i.e. elevating the chin away from the chest). The carotid sinus is normally positioned inferior to the angle of the jaw, near the arterial impulse, at the level of the thyroid cartilage. For 5 to 10 seconds, pressure is administered to one carotid sinus. Although pulsatile pressure applied in a vigorous circular motion may be more effective, continuous pressure is preferred since it is more reproducible. If the predicted reaction is not obtained, the operation is repeated on the opposite side after a one- to two-minute wait.
-
This question is part of the following fields:
- Anatomy
- Head And Neck
-
-
Question 18
Incorrect
-
Which of the following muscles are primarily involved in passive inspiration:
Your Answer:
Correct Answer: Diaphragm and external intercostal muscles
Explanation:Passive inspiration is produced by contraction of the diaphragm (depressing the diaphragm) and the external intercostal muscles (elevating the ribs). In inspiration, elevation of the sternal ends of the ribs (‘pump handle’ movement), elevation of the lateral shafts of the ribs (‘bucket handle’ movement) and depression of the diaphragm result in expansion of the thorax in an anteroposterior, transverse and vertical direction respectively. This results in an increased intrathoracic volume and decreased intrathoracic pressure and thus air is drawn into the lungs.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 19
Incorrect
-
ACE inhibitors are indicated for all of the following EXCEPT for:
Your Answer:
Correct Answer: Angina
Explanation:ACE inhibitors have many uses and are generally well tolerated. They are indicated for:Heart failureHypertensionDiabetic nephropathySecondary prevention of cardiovascular events
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 20
Incorrect
-
In relation to ketamine, which of the following statements is TRUE:
Your Answer:
Correct Answer: It is usually associated with tachycardia, increased blood pressure and increased cardiac output.
Explanation:Ketamine has hypnotic, analgesic and local anaesthetic properties. Major adverse effects include Hypertension, Increased cardiac output, Increased ICP, Tachycardia, Tonic-clonic movements, Visual hallucinations and Vivid dreams.Ketamine is mostly utilized in paediatric anaesthesia, especially when repeated dosing is necessary (such as for serial burns dressings). Ketamine has little effect on respiratory drive, and protective airway reflexes are unaffected. Ketamine is also a bronchial smooth muscle relaxant, hence it plays a unique function in the treatment of severe asthma.
-
This question is part of the following fields:
- Anaesthesia
- Pharmacology
-
-
Question 21
Incorrect
-
A patient presents with a cough, productive of green sputum and fever. He was commenced on antibiotics 4 days earlier, but his condition has worsened. There is a documented history of penicillin allergy, and the GP prescribed erythromycin.Erythromycin exert its pharmacological effect by binding to?
Your Answer:
Correct Answer: The 50S subunit of the bacterial ribosome
Explanation:Macrolides are bacteriostatic antibiotics. They act by binding to the 50S subunit of the bacterial ribosome and inhibit translocation, therefore, inhibiting protein synthesis.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 22
Incorrect
-
If the ejection fraction increases, there will be a decrease in:
Your Answer:
Correct Answer: End-systolic volume
Explanation:An increase in ejection fraction means that a higher fraction of the end-diastolic volume is ejected in the stroke volume (e.g. because of the administration of a positive inotropic agent). When this situation occurs, the volume remaining in the ventricle after systole, the end-systolic volume, will be reduced. Cardiac output, stroke volume, and mean arterial pressure will be increased.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 23
Incorrect
-
You are taking care of a 55-year-old male patient with a direct inguinal hernia. In explaining his hernia, which of the following layers was compromised and had resulted in his condition?
Your Answer:
Correct Answer: Transversalis fascia
Explanation:Direct inguinal hernias are most often caused by a weakness in the muscles of the abdominal wall that develops over time, or are due to straining or heavy lifting. A direct inguinal hernia protrudes through the Transversalis fascia.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 24
Incorrect
-
You note that the prostate of a 60-year-old patient is enlarged during the examination. You suspect BPH. Anatomically, the prostate has four main lobes. Which of the lobes is affected by benign prostatic hypertrophy?
Your Answer:
Correct Answer: Median lobe
Explanation:Benign prostatic hyperplasia (BPH), also known as benign prostatic hypertrophy, is characterized by an enlarged prostate gland. The prostate is divided into four major lobes. The median lobe is the most commonly affected by benign prostatic enlargement, resulting in urethral obstruction and urine symptoms.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 25
Incorrect
-
Regarding Clostridium species, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: They are facultative anaerobes.
Explanation:Clostridium spp. are obligatory anaerobic spore-forming Gram-positive bacilli. Toxin production is the main pathogenicity mechanism.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 26
Incorrect
-
An injury to which nerve affects innervation to the adductor portion of the adductor magnus?
Your Answer:
Correct Answer: Posterior branch of the obturator nerve
Explanation:The nerves that supply the adductor magnus muscle have an embryologic origin from the anterior divisions of the lumbosacral plexus and include the obturator nerve, posterior division (L2-4), and the tibial portion of the sciatic nerve (L4). It is innervated by the posterior division of the obturator nerve.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 27
Incorrect
-
A 32-old woman comes for a follow-up visit after being discharged on medications for her newly diagnosed epilepsy. She now complains of a tremor in her arm when she holds a tray in her hand. You examine the patient and notice she has developed postural tremors. Which of the following medications for epilepsy is most likely responsible for this tremor?
Your Answer:
Correct Answer: Sodium valproate
Explanation:A postural tumour is observed when a person maintains a position against gravity, such as holding the arms outstretched. (The patient holding her tray against gravity) Sodium valproate is the most commonly prescribed medication for epilepsy. It is commonly associated with tremors as valproate-induced tremors occur in around 6-45% of patients. The tremors are commonly postural, but a resting tremor may also occur.Approximately 25% of patients taking sodium valproate are found to develop a tremor within 3-12 months of initiating therapy.
-
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
-
-
Question 28
Incorrect
-
Which of the following is characterised by passive carrier-mediated transport down a chemical concentration gradient:
Your Answer:
Correct Answer: Facilitated diffusion
Explanation:Facilitated diffusion is the process of spontaneous passive transport of molecules or ions down their concentration gradient across a cell membrane via specific transmembrane transporter (carrier) proteins. The energy required for conformational changes in the transporter protein is provided by the concentration gradient rather than by metabolic activity.
-
This question is part of the following fields:
- Basic Cellular
- Physiology
-
-
Question 29
Incorrect
-
Which of these organisms is commonly spread by droplet transmission?
Your Answer:
Correct Answer: Neisseria meningitidis
Explanation:Droplets are airborne particles greater than 5 µm in size. Droplet transmission occurs during talking, coughing and sneezing where respiratory droplets are generated.Examples of organisms transmitted by the droplet route include:Neisseria meningitidisRespiratory syncytial virusParainfluenza virusBordetella pertussisInfluenza virusPoliovirus and Rotavirus are transmitted by the faeco-oral routeHepatitis B is transmitted by Sexual routeStaphylococcus aureus is transmitted by direct contact
-
This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
-
-
Question 30
Incorrect
-
An ambulance transports a 23-year-old woman who has taken a witnessed overdose of her mother's diazepam tablets. She has no significant medical history and does not take any medications on a regular basis.In this case, what is the SINGLE MOST APPROPRIATE FIRST DRUG TREATMENT?
Your Answer:
Correct Answer: Flumazenil IV 200 μg
Explanation:Flumazenil is a benzodiazepine antagonist that can be helpful in some overdose situations. It works quickly (in less than a minute), but the effects are fleeting, lasting less than an hour. The dose is 200 micrograms every 1-2 minutes with a maximum dose of 3 milligrams per hour.Flumazenil should be avoided by patients who are addicted to benzodiazepines or who take tricyclic antidepressants because it can cause withdrawal symptoms. It can cause seizures or cardiac arrest in these situations.
-
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
-
SESSION STATS - PERFORMANCE PER SPECIALTY
