-
Question 1
Incorrect
-
A patient suffers a stab wound to the neck. The entry point of the blade is situated within the anterior triangle of the neck.Which of the following muscles is most likely to be involved? Select ONE answer only.
Your Answer: Sternocleidomastoid
Correct Answer: Sternohyoid
Explanation:The anterior triangle is the triangular area of the neck found anteriorly to the sternocleidomastoid muscle. It is formed by the anterior border of sternocleidomastoid laterally, the median line of the neck medially and by the inferior border of the mandible superiorly. The apex of the anterior triangle extends towards the manubrium sterni. The anterior triangle contains:Muscles: thyrohyoid, sternothyroid, sternohyoid musclesOrgans: thyroid gland, parathyroid glands, larynx, trachea, esophagus, submandibular gland, caudal part of the parotid glandArteries: superior and inferior thyroid, common carotid, external carotid, internal carotid artery (and sinus), facial, submental, lingual arteriesVeins: anterior jugular veins, internal jugular, common facial, lingual, superior thyroid, middle thyroid veins, facial vein, submental vein, lingual veinsNerves: vagus nerve (CN X), hypoglossal nerve (CN XII), part of sympathetic trunk, mylohyoid nerveThe posterior triangle is a triangular area found posteriorly to the sternocleidomastoid muscle. It has three borders; anterior, posterior and inferior borders. The anterior border is the posterior margin of the sternocleidomastoid muscle. The posterior border is the anterior margin of the trapezius muscle, while the inferior border is the middle one-third of the clavicle. The investing layer of deep cervical fascia and integument forms the roof of the space, while the floor is covered with the prevertebral fascia along with levator scapulae, splenius capitis and the scalene muscles. The inferior belly of omohyoid subdivides the posterior triangle into a small supraclavicular, and a large occipital, triangle.Contents:Vessels: the third part of the subclavian artery, suprascapular and transverse cervical branches of the thyrocervical trunk, external jugular vein, lymph nodesNerves: accessory nerve (CN XI), the trunks of the brachial plexus, fibers of the cervical plexus
-
This question is part of the following fields:
- Anatomy
- Head And Neck
-
-
Question 2
Correct
-
All of the following are indications for beta-blockers EXCEPT for:
Your Answer: Prinzmetal's angina
Explanation:Beta-blockers are contraindicated in Prinzmetal’s angina.Beta-blockers may be indicated in:HypertensionPheochromocytoma (only with an alpha-blocker)AnginaSecondary prevention after ACSArrhythmias including atrial fibrillationHeart failureThyrotoxicosisAnxietyProphylaxis of migraineEssential tremorGlaucoma
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 3
Correct
-
What is the mechanism of action of penicillin antibiotics:
Your Answer: Inhibition of bacterial cell wall synthesis
Explanation:Penicillins and the other ß-lactam antibiotics are bactericidal. They produce their antimicrobial action by preventing cross-linkage between the linear peptidoglycan polymer chains that make up the bacterial cell wall. They, therefore, inhibit cell wall synthesis.The integrity of the ß-lactam ring is essential for antimicrobial activity. Many bacteria (including most Staphylococci) are resistant to benzylpenicillin and phenoxymethylpenicillin because they produce enzymes (penicillinases, ß-lactamases) that open the ß-lactam ring.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 4
Correct
-
All of the following statements regarding Helicobacter pylori is considered true, except:
Your Answer: Serum antibody levels should be used to check for successful eradication
Explanation:Helicobacter pylori is a curved, non-spore forming, Gram-negative bacteria that is primarily linked to gastric infections. Once acquired, it colonizes the stomach for a long time and can cause a low-grade inflammatory process, producing a chronic superficial gastritis.H. pylori can be recovered from gastric biopsy materials. Samples must be transported quickly to the laboratory.Helicobacter infections usually are identified by nonculture methods. H. pylori can be presumptively identified in a gastric biopsy specimen by testing for the presence of a rapid urease reaction.Serologic testing is an important screening method for the diagnosis of H. pylori infection. It can also be diagnosed by faecal antigen detection, microscopic examination of stained gastric tissue, and DNA amplification tests.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 5
Correct
-
A 60-year-old man diagnosed with chronic kidney disease has an elevated creatinine level and a reduced glomerular filtration rate (GFR).Which statement concerning glomerular filtration is true?
Your Answer: Creatinine is freely filtered at the glomerulus
Explanation:Glomerular filtration is a passive process. It depends on the net hydrostatic pressure across the glomerular capillaries, the oncotic pressure, and the intrinsic permeability of the glomerulus.The mean values for glomerular filtration rate (GFR) in young adults are 130 ml/min/1.73m2 in males and 120 ml/min/1.73m2in females.The GFR declines with age after the age of 40 at a rate of approximately 1 ml/min/year.The Cockcroft and Gault formula overestimates creatinine in obese patients. This is because their endogenous creatinine production is less than that predicted by overall body weight.Creatinine is used in the estimation of GFR because it is naturally produced by muscle breakdown, not toxic, not produced by the kidney, freely filtered at the glomerulus, not reabsorbed from the nephron, and does not alter GFR.
-
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 6
Incorrect
-
Regarding the lacrimal apparatus, which of the following statements is CORRECT:
Your Answer: The lacrimal gland is located in the superomedial region of the orbit.
Correct Answer: Lacrimal fluid is drained from the eyeball through the lacrimal punctum.
Explanation:Lacrimal fluid is drained from the eyeball through the lacrimal punctum.
-
This question is part of the following fields:
- Anatomy
- Head And Neck
-
-
Question 7
Correct
-
During swallowing, which of the following structures primarily closes the tracheal opening:
Your Answer: Epiglottis
Explanation:The vocal cords of the larynx are stronglyapproximated, and the larynx is pulled upwardand anteriorly by the neck muscles. These actions,combined with the presence of ligaments thatprevent upward movement of the epiglottis, causethe epiglottis to swing back over the openingof the larynx. All these effects acting togetherprevent the passage of food into the nose andtrachea. Most essential is the tight approximationof the vocal cords, but the epiglottis helps toprevent food from ever getting as far as the vocalcords. Destruction of the vocal cords or of themuscles that approximate them can causestrangulation.
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 8
Correct
-
An elderly female has a bacterial infection and you are asked to prescribe an antibiotic to her. This antibiotic is a nucleic acid synthesis inhibitor.Which of the following antimicrobial drugs will be prescribed to this patient?
Your Answer: Metronidazole
Explanation:Metronidazole and the other 5-nitroimidazole agents inhibit nucleic acid synthesis by forming toxic free radical metabolites in the bacterial cell that damage DNA. Vancomycin inhibits cell wall peptidoglycan formation by binding the D-Ala-D-Ala portion of cell wall precursors. Erythromycin inhibits protein synthesis and blocks translocation by binding to the 23S rRNA of the 50S ribosomal subunit.Chloramphenicol blocks peptidyl transferase at 50S ribosomal subunit.Gentamicin, an aminoglycoside antibiotic, acts by binding to the 30S subunit of the bacterial ribosome inhibiting the binding of aminoacyl-tRNA and thus preventing initiation of protein synthesis.An overview of the different mechanisms of action of the various types of antimicrobial agents is shown below:1. Inhibition of cell wall synthesis- Penicillins- Cephalosporins- Vancomycin2. Disruption of cell membrane function- Polymyxins- Nystatin- Amphotericin B3. Inhibition of protein synthesis- Macrolides- Aminoglycosides- Tetracyclines- Chloramphenicol4. Inhibition of nucleic acid synthesis- Quinolones- Trimethoprim- 5-nitroimidazoles- Rifampicin5. Anti-metabolic activity- Sulphonamides- Isoniazid
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 9
Incorrect
-
A patient presents with a necrolytic migratory rash. Her blood serum glucagon concentration is 1246 pg/mL. Following further investigations, she is diagnosed with glucagonoma.Which SINGLE statement regarding glucagon is true?
Your Answer: Its secretion is inhibited by adrenaline
Correct Answer: It makes fatty acids available for oxidation
Explanation:Glucagon is a peptide hormone that is produced and secreted by alpha cells of the islets of Langerhans, which are located in the endocrine portion of the pancreas. The main physiological role of glucagon is to stimulate hepatic glucose output, thereby leading to increases in glycaemia. It provides the major counter-regulatory mechanism to insulin in maintaining glucose homeostasis.Hypoglycaemia is the principal stimulus for the secretion of glucagon but may also be used as an antidote in beta-blocker overdose and in anaphylaxis in patients on beta-blockers that fail to respond to adrenaline. Glucagon then causes:GlycogenolysisGluconeogenesisLipolysis in adipose tissueThe secretion of glucagon is also stimulated by:AdrenalineCholecystokininArginineAlanineAcetylcholineThe secretion of glucagon is inhibited by:InsulinSomatostatinIncreased free fatty acidsIncreased urea productionGlycolysis is the metabolic pathway that converts glucose into pyruvate. The free energy released by this process is used to form ATP and NADH. Glycolysis is inhibited by glucagon, and glycolysis and gluconeogenesis are reciprocally regulated so that when one cell pathway is activated, the other is inactive and vice versa.Glucagon has a minor effect of enhancing lipolysis in adipose tissue. Lipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and free fatty acids. It makes fatty acids available for oxidation.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 10
Incorrect
-
Which of the following ligaments supports the head of the talus?
Your Answer: Calcaneofibular ligament
Correct Answer: Spring ligament
Explanation:The spring-ligament complex is a significant medial arch stabilizer. The two important functions of this ligament include promoting the stability of the talonavicular joint by acting as a support for the talus head and by acting as a static support to maintain the medial longitudinal arch.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 11
Incorrect
-
A 58-year-old man with a traumatic brain injury is brought into the ER. A medical student asks you about the processes that occur in the brain following a traumatic injury.One of these best describes the central nervous systems response to injury.
Your Answer: Microglia undergo reactive gliosis to leave behind firm translucent tissue
Correct Answer: Degeneration of the axon occurs proximally before it occurs distally
Explanation:Following neuronal injury, as seen in traumatic brain injury, the axon undergoes anterograde degeneration. Degradation starts from the cell body (proximally) and progresses distally. The axon becomes fragmented and degenerates. The brain shows no reactive changes to injury is incorrect. Following major injury such as stroke, the brain undergoes a process of liquefactive degeneration, which leaves cystic spaces within the brain.Axonal regeneration does not occur to any significant extent within the central nervous system unlike what is seen in the peripheral nervous system. Astrocytes undergo reactive gliosis, leaving behind a firm translucent tissue around sites of damage.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 12
Incorrect
-
A 20-year-old boy took almost 25 tablets of paracetamol almost 4 hours ago. The boy is healthy and has no known comorbid or drug history. Out of the following metabolic pathways, which one is primarily responsible for the toxic effects of paracetamol?
Your Answer: First-pass metabolism
Correct Answer: N-hydroxylation
Explanation:Paracetamol is predominantly metabolized in the liver by three main metabolic pathways:1. Glucuronidation (45-55%)2. Sulphate conjugation (30-35%)3. N-hydroxylation via the hepatic cytochrome P450 enzyme system (10-15%)Cytochrome P450 enzymes catalyse the oxidation of acetaminophen to the reactive metabolite N-acetyl-p-benzoquinoneimine (NAPQI). NAPQI primarily contributes to the toxic effects of acetaminophen. NAPQI is an intermediate metabolite that is further metabolized by fast conjugation with glutathione. The conjugated metabolite is then excreted in the urine as mercapturic acid. High doses of acetaminophen (overdoses) can lead to hepatic necrosis due to depleting glutathione and high binding levels of reactive metabolite (NAPQI) to important parts of liver cells.
-
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
-
-
Question 13
Correct
-
Regarding fat digestion, which of the following statements is CORRECT:
Your Answer: Chylomicrons are exocytosed from enterocytes to enter lacteals and thus the lymphatic system.
Explanation:Dietary fat is chiefly composed of triglycerides (esters of free fatty acids and glycerol which may be saturated or unsaturated). The essential fatty acids are linoleic acid and alpha-linoleic acid, which cannot be manufactured in the body. Dietary fat provides 37 kJ (9 kcal) of energy per gram. Fats are digested almost entirely in the small intestine and are only released from the stomach into the duodenum at the rate at which they can be digested.Pancreatic lipase is the most significant enzyme for fat digestion. In the duodenum fat is emulsified by bile acids, a process where larger lipid droplets are broken down into much smaller droplets providing a greater surface area for enzymatic digestion. Micelles are arranged so that hydrophobic lipid molecules lie in the centre, surrounded by bile acids arranged such the outer region is hydrophilic. Dietary and synthesised lipids are incorporated into chylomicrons in the Golgi body, which are exocytosed from the basolateral membrane to enter lacteals and thus the lymphatic system.
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 14
Correct
-
Regarding dermatophytes, which of the following statement is CORRECT:
Your Answer: Diagnosis is made from microscopy and culture of skin scrapings, hair samples or nail clippings.
Explanation:Diagnosis is made from microscopy and culture of skin scrapings, hair samples or nail clippings depending on the site of infection. The lesions of ringworm typically have a dark outer ring with a pale centre. Tinea capitis is ringworm affecting the head and scalp. Spread is via direct skin contact. Treatment is usually topical, oral antifungals are reserved for refractory infection.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 15
Incorrect
-
A 24-year-old man goes to the emergency department with a fever, headache, and swollen parotid glands that are excruciating. You have a suspicion that it is mumps. Which of the following nerves is causing the discomfort the patient is experiencing:
Your Answer: Facial nerve
Correct Answer: Auriculotemporal nerve
Explanation:The auriculotemporal nerve is irritated by mumps, which results in significant discomfort due to inflammation and swelling of the parotid gland, as well as the stretching of its capsule. Compression caused by swallowing or chewing exacerbates pain.
-
This question is part of the following fields:
- Anatomy
- Head And Neck
-
-
Question 16
Correct
-
Question 17
Incorrect
-
A 70-year-old woman presents with right-sided loss of pain and temperature sense on the body as well as left-sided loss of pain and temperature sense on the face. She also has complaints of vertigo, nausea, and tinnitus. Further examination of her cranial nerves suggest the presence of Horner's Syndrome. An MRI and CT scan was ordered and results showed that she is suffering from a left-sided stroke. Branches of which of the following arteries are most likely implicated in the case?
Your Answer: Vertebral artery
Correct Answer: Posterior inferior cerebellar artery
Explanation:Wallenberg syndrome is also known as lateral medullary syndrome and posterior inferior cerebellar artery syndrome. It is the most common posterior circulation ischemic stroke syndrome. The primary pathology of Wallenberg syndrome is occlusion of the posterior inferior cerebellar artery (PICA) or one of its branches.It is characterized by vertigo with nystagmus, nausea and vomiting, and sometimes hiccups, dysphonia, dysarthria, and dysphagia often present with ipsilateral loss of gag reflex, ipsilateral ataxia with a tendency to fall to the ipsilateral side, pain and numbness with impaired facial sensation on the face, impaired taste sensation, and impaired pain and temperature sensation in the arms and legs.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 18
Correct
-
A 67-year-old man with chronic breathlessness is sent for a lung function test.Which statement concerning lung function testing is true?
Your Answer: In restrictive lung disease, the FEV 1 /FVC ratio is usually >0.7
Explanation:In restrictive lung disease, the FEV1/FVC ratio is usually >0.7%.In obstructive lung disease, FEV1 is reduced to <80% of normal and FVC is usually reduced. The FEV1/FVC ratio is reduced to 80% in the presence of symptomsModerate airflow obstruction = FEV 1 of 50-79%Severe airflow obstruction = FEV 1 of 30-49%Very severe airflow obstruction = FEV1<30%.Spirometry is a poor predictor of quality of life in COPD. However, it can be used as part of the assessment of severity of COPD.
-
This question is part of the following fields:
- Physiology
- Respiratory Physiology
-
-
Question 19
Incorrect
-
A 27 year old woman presents to ED having sustained a deep laceration to the dorsum of her ring finger whilst cooking. Her proximal interphalangeal joint is fixed in flexion and the distal interphalangeal joint is hyperextended. Which of the following structures in the digit has most likely been injured:
Your Answer: Superficial branch of the radial nerve
Correct Answer: Insertion of the central slip of the extensor tendon
Explanation:Damage to the central slip of the extensor digitorum tendon would result in loss of extension at the proximal interphalangeal joint resulting in a fixed flexion deformity of this joint, and hyperextension of the distal interphalangeal joint due to a loss of balancing forces. This is called the Boutonniere deformity.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 20
Correct
SESSION STATS - PERFORMANCE PER SPECIALTY
