00
Correct
00
Incorrect
00 : 00 : 00
Session Time
00 : 00
Average Question Time ( Secs)
  • Question 1 - Sarah, a 25-year-old type 1 diabetic, is interested in joining a local running...

    Incorrect

    • Sarah, a 25-year-old type 1 diabetic, is interested in joining a local running group. As her physician, it is important to inform her of the potential impact this increase in physical activity may have on her blood sugar levels. What advice do you give her?

      Your Answer: She is at risk of an early drop due to glucose uptake and a late rise hours later due to adrenaline secretion

      Correct Answer: She is at risk of an early and a late drop, hours later, in her blood glucose due muscle uptake and replacement of glycogen

      Explanation:

      Glucose levels are impacted by exercise in various ways. Firstly, there is an initial decrease due to the increased uptake of glucose in the muscles through GLUT-2, which does not require insulin. Secondly, during high-intensity sports, the release of adrenaline and cortisol can cause a temporary increase in blood glucose levels, especially during competitive events. Finally, there is a delayed decrease as the muscles and liver glycogen are utilized during exercise and then replenished over the following hours.

      Glycogenesis – the process of storing glucose as glycogen

      Glycogenesis is the process of converting glucose into glycogen for storage in the liver and muscles. This process is important for maintaining blood glucose levels and providing energy during times of fasting or exercise. The key enzyme involved in glycogenesis is glycogen synthase, which catalyzes the formation of α-1,4-glycosidic bonds between glucose molecules to form glycogen. Branching enzyme then creates α-1,6-glycosidic bonds to form branches in the glycogen molecule. Glycogenin, a protein that acts as a primer for glycogen synthesis, is also involved in the process. Glycogenesis is regulated by hormones such as insulin and glucagon, which stimulate and inhibit glycogen synthesis, respectively. Understanding the process of glycogenesis is important for understanding how the body stores and utilizes glucose for energy.

    • This question is part of the following fields:

      • Endocrine System
      20.7
      Seconds
  • Question 2 - You are on a post-take ward round with your consultant and review a...

    Incorrect

    • You are on a post-take ward round with your consultant and review a 50-year-old man who was admitted with sudden severe abdominal pain, confusion and pyrexia. He has a history of alcoholic cirrhosis and known asymptomatic ascites. An ascitic tap was performed overnight which revealed a neutrophil count of 375/mm³ and was sent for urgent microscopy & culture.

      What is the most probable organism to be cultured from the ascitic tap?

      Your Answer: Enterococcus

      Correct Answer: E. coli

      Explanation:

      The most frequently isolated organism in ascitic fluid culture in cases of spontaneous bacterial peritonitis is E. coli. While Staphylococcus aureus, Klebsiella, and Streptococcus can also cause spontaneous bacterial peritonitis, they are not as commonly found as E. coli.

      Understanding Spontaneous Bacterial Peritonitis

      Spontaneous bacterial peritonitis (SBP) is a type of peritonitis that typically affects individuals with ascites caused by liver cirrhosis. The condition is characterized by symptoms such as abdominal pain, fever, and ascites. Diagnosis is usually made through paracentesis, which reveals a neutrophil count of over 250 cells/ul. The most common organism found on ascitic fluid culture is E. coli.

      Management of SBP typically involves the administration of intravenous cefotaxime. Antibiotic prophylaxis is recommended for patients with ascites who have had an episode of SBP or have fluid protein levels below 15 g/l and a Child-Pugh score of at least 9 or hepatorenal syndrome. NICE recommends prophylactic oral ciprofloxacin or norfloxacin until the ascites has resolved.

      Alcoholic liver disease is a significant predictor of poor prognosis in SBP. Understanding the symptoms, diagnosis, and management of SBP is crucial for healthcare professionals to provide appropriate care for patients with this condition. Proper management can help improve outcomes and prevent complications.

    • This question is part of the following fields:

      • Gastrointestinal System
      6.4
      Seconds
  • Question 3 - A 62-year-old male with type 2 diabetes is urgently referred by his GP...

    Incorrect

    • A 62-year-old male with type 2 diabetes is urgently referred by his GP due to poor glycaemic control for the past three days, with home blood glucose readings around 25 mmol/L. He is currently being treated with metformin and lisinopril. Yesterday, his GP checked his U+E and found that his serum sodium was 138 mmol/L (137-144), serum potassium was 5.8 mmol/L (3.5-4.9), serum urea was 20 mmol/L (2.5-7.5), and serum creatinine was 350 µmol/L (60-110). On examination, he has a temperature of 39°C, a pulse of 108 bpm, a blood pressure of 96/60 mmHg, a respiratory rate of 32/min, and oxygen saturations of 99% on air. His cardiovascular, respiratory, and abdominal examination are otherwise normal. Further investigations reveal a plasma glucose level of 17 mmol/L (3.0-6.0) and urine analysis showing blood ++ and protein ++, but ketones are negative. What is the likely diagnosis?

      Your Answer:

      Correct Answer: Sepsis

      Explanation:

      The causes of septic shock are important to understand in order to provide appropriate treatment and improve patient outcomes. Septic shock can cause fever, hypotension, and renal failure, as well as tachypnea due to metabolic acidosis. However, it is crucial to rule out other conditions such as hyperosmolar hyperglycemic state or diabetic ketoacidosis, which have different symptoms and diagnostic criteria.

      While metformin can contribute to acidosis, it is unlikely to be the primary cause in this case. Diabetic patients may be prone to renal tubular acidosis, but this is not likely to be the cause of an acute presentation. Instead, a type IV renal tubular acidosis, characterized by hyporeninaemic hypoaldosteronism, may be a more likely association.

      Overall, it is crucial to carefully evaluate patients with septic shock and consider all possible causes of their symptoms. By ruling out other conditions and identifying the underlying cause of the acidosis, healthcare providers can provide targeted treatment and improve patient outcomes. Further research and education on septic shock and its causes can also help to improve diagnosis and treatment in the future.

    • This question is part of the following fields:

      • Renal System
      0
      Seconds
  • Question 4 - A 44-year-old woman with a history of multiple sclerosis (MS) visits her GP...

    Incorrect

    • A 44-year-old woman with a history of multiple sclerosis (MS) visits her GP with a complaint of eating difficulties. During the examination, the GP observes a noticeable elevation of the mandible when striking the base of it. Which cranial nerve provides the afferent limb to this reflex?

      Your Answer:

      Correct Answer: CN V3

      Explanation:

      Cranial nerves are a set of 12 nerves that emerge from the brain and control various functions of the head and neck. Each nerve has a specific function, such as smell, sight, eye movement, facial sensation, and tongue movement. Some nerves are sensory, some are motor, and some are both. A useful mnemonic to remember the order of the nerves is Some Say Marry Money But My Brother Says Big Brains Matter Most, with S representing sensory, M representing motor, and B representing both.

      In addition to their specific functions, cranial nerves also play a role in various reflexes. These reflexes involve an afferent limb, which carries sensory information to the brain, and an efferent limb, which carries motor information from the brain to the muscles. Examples of cranial nerve reflexes include the corneal reflex, jaw jerk, gag reflex, carotid sinus reflex, pupillary light reflex, and lacrimation reflex. Understanding the functions and reflexes of the cranial nerves is important in diagnosing and treating neurological disorders.

    • This question is part of the following fields:

      • Neurological System
      0
      Seconds
  • Question 5 - A 32-year-old man has been struck by a cricket ball on the medial...

    Incorrect

    • A 32-year-old man has been struck by a cricket ball on the medial side of his elbow, resulting in significant pain. Additionally, he has experienced numbness in his little finger. Despite x-rays showing no immediate fractures, there is severe swelling in the soft tissue. When requested to adduct his thumb, he is unable to do so. Which nerve is the most likely culprit for the damage?

      Your Answer:

      Correct Answer: Ulnar nerve

      Explanation:

      The ulnar nerve provides innervation to the adductor pollicis muscle, so any injury to the ulnar nerve can lead to a loss of adduction in the thumb.

      The ulnar nerve originates from the medial cord of the brachial plexus, specifically from the C8 and T1 nerve roots. It provides motor innervation to various muscles in the hand, including the medial two lumbricals, adductor pollicis, interossei, hypothenar muscles (abductor digiti minimi, flexor digiti minimi), and flexor carpi ulnaris. Sensory innervation is also provided to the medial 1 1/2 fingers on both the palmar and dorsal aspects. The nerve travels through the posteromedial aspect of the upper arm and enters the palm of the hand via Guyon’s canal, which is located superficial to the flexor retinaculum and lateral to the pisiform bone.

      The ulnar nerve has several branches that supply different muscles and areas of the hand. The muscular branch provides innervation to the flexor carpi ulnaris and the medial half of the flexor digitorum profundus. The palmar cutaneous branch arises near the middle of the forearm and supplies the skin on the medial part of the palm, while the dorsal cutaneous branch supplies the dorsal surface of the medial part of the hand. The superficial branch provides cutaneous fibers to the anterior surfaces of the medial one and one-half digits, and the deep branch supplies the hypothenar muscles, all the interosseous muscles, the third and fourth lumbricals, the adductor pollicis, and the medial head of the flexor pollicis brevis.

      Damage to the ulnar nerve at the wrist can result in a claw hand deformity, where there is hyperextension of the metacarpophalangeal joints and flexion at the distal and proximal interphalangeal joints of the 4th and 5th digits. There may also be wasting and paralysis of intrinsic hand muscles (except for the lateral two lumbricals), hypothenar muscles, and sensory loss to the medial 1 1/2 fingers on both the palmar and dorsal aspects. Damage to the nerve at the elbow can result in similar symptoms, but with the addition of radial deviation of the wrist. It is important to diagnose and treat ulnar nerve damage promptly to prevent long-term complications.

    • This question is part of the following fields:

      • Neurological System
      0
      Seconds
  • Question 6 - A 32-year-old man is recuperating on the ward after undergoing surgery on his...

    Incorrect

    • A 32-year-old man is recuperating on the ward after undergoing surgery on his parotid gland. During the ward round, it is observed that he has weakness on the right side of his face. The right side of his forehead lacks wrinkles, and he has difficulty closing his right eye. However, he still has naso-labial folds, and there is no drooping of the mouth. Which branch of the facial nerve is most likely affected by the damage?

      Your Answer:

      Correct Answer: Temporal branch

      Explanation:

      The muscles of facial expression are innervated by the facial nerve, which has five branches: the temporal branch, zygomatic branch, buccal branch, marginal mandibular branch, and cervical branch. The temporal branch specifically provides innervation to the frontalis muscle, which raises the eyebrows and wrinkles the forehead, the corrugator supercilii muscle, which assists in frowning by drawing the eyebrows inferomedially, and the orbicularis oculi muscle, which is responsible for closing the eyelids. During parotid surgery, it is important to be cautious and avoid damaging the facial nerve, which branches within the parotid gland but does not supply it.

      The facial nerve is responsible for supplying the muscles of facial expression, the digastric muscle, and various glandular structures. It also contains a few afferent fibers that originate in the genicular ganglion and are involved in taste. Bilateral facial nerve palsy can be caused by conditions such as sarcoidosis, Guillain-Barre syndrome, Lyme disease, and bilateral acoustic neuromas. Unilateral facial nerve palsy can be caused by these conditions as well as lower motor neuron issues like Bell’s palsy and upper motor neuron issues like stroke.

      The upper motor neuron lesion typically spares the upper face, specifically the forehead, while a lower motor neuron lesion affects all facial muscles. The facial nerve’s path includes the subarachnoid path, where it originates in the pons and passes through the petrous temporal bone into the internal auditory meatus with the vestibulocochlear nerve. The facial canal path passes superior to the vestibule of the inner ear and contains the geniculate ganglion at the medial aspect of the middle ear. The stylomastoid foramen is where the nerve passes through the tympanic cavity anteriorly and the mastoid antrum posteriorly, and it also includes the posterior auricular nerve and branch to the posterior belly of the digastric and stylohyoid muscle.

    • This question is part of the following fields:

      • Neurological System
      0
      Seconds
  • Question 7 - A 75-year-old male with a history of atrial fibrillation and diverticulitis presents to...

    Incorrect

    • A 75-year-old male with a history of atrial fibrillation and diverticulitis presents to the emergency department with severe abdominal pain. After thorough investigation, including mesenteric angiography, it was found that the left colic flexure was experiencing ischemia. Which artery provides direct supply to this region through its branches?

      Your Answer:

      Correct Answer: Inferior mesenteric artery (IMA)

      Explanation:

      The inferior mesenteric artery supplies the distal 1/3 of the transverse colon, while the proximal two thirds are supplied by the middle colic artery, a branch of the SMA. The left colic artery, a branch of the IMA, supplies the remaining distal portion. Although the left colic artery is the primary supplier, collateral flow from branches of the middle colic artery also contributes. The left colic flexure, located between the end of the SMA and the start of the IMA’s blood supply, is a watershed region that can be susceptible to ischemia due to atherosclerotic changes or hypotension.

      The splenic artery directly supplies the spleen and also has branches that supply the stomach and pancreas. There is no such thing as the AMA or PMA.

      The Transverse Colon: Anatomy and Relations

      The transverse colon is a part of the large intestine that begins at the hepatic flexure, where the right colon makes a sharp turn. At this point, it becomes intraperitoneal and is connected to the inferior border of the pancreas by the transverse mesocolon. The middle colic artery and vein are contained within the mesentery. The greater omentum is attached to the superior aspect of the transverse colon, which can be easily separated. The colon undergoes another sharp turn at the splenic flexure, where the greater omentum remains attached up to this point. The distal 1/3 of the transverse colon is supplied by the inferior mesenteric artery.

      The transverse colon is related to various structures. Superiorly, it is in contact with the liver, gallbladder, the greater curvature of the stomach, and the lower end of the spleen. Inferiorly, it is related to the small intestine. Anteriorly, it is in contact with the greater omentum, while posteriorly, it is in contact with the descending portion of the duodenum, the head of the pancreas, convolutions of the jejunum and ileum, and the spleen. Understanding the anatomy and relations of the transverse colon is important for medical professionals in diagnosing and treating various gastrointestinal conditions.

    • This question is part of the following fields:

      • Gastrointestinal System
      0
      Seconds
  • Question 8 - A 10-year-old girl has been diagnosed with asthma. Her father asks you about...

    Incorrect

    • A 10-year-old girl has been diagnosed with asthma. Her father asks you about the cause of her symptoms. What is the best response?

      Inflammation of the lining of the bronchioles causes obstruction of the flow of air out from the lungs. This inflammation is reversible so symptoms of asthma may be intermittent. There may also be increased mucus production and bronchial muscle constriction.

      Your Answer:

      Correct Answer: Reversible inflammation of the lining of the small airways causing them to become narrower

      Explanation:

      The bronchioles’ lining inflammation obstructs the outflow of air from the lungs, leading to asthma symptoms that may come and go. Additionally, there could be heightened mucus production and constriction of bronchial muscles.

      Asthma is a common respiratory disorder that affects both children and adults. It is characterized by chronic inflammation of the airways, resulting in reversible bronchospasm and airway obstruction. While asthma can develop at any age, it typically presents in childhood and may improve or resolve with age. However, it can also persist into adulthood and cause significant morbidity, with around 1,000 deaths per year in the UK.

      Several risk factors can increase the likelihood of developing asthma, including a personal or family history of atopy, antenatal factors such as maternal smoking or viral infections, low birth weight, not being breastfed, exposure to allergens and air pollution, and the hygiene hypothesis. Patients with asthma may also suffer from other atopic conditions such as eczema and hay fever, and some may be sensitive to aspirin. Occupational asthma is also a concern for those exposed to allergens in the workplace.

      Symptoms of asthma include coughing, dyspnea, wheezing, and chest tightness, with coughing often worse at night. Signs may include expiratory wheezing on auscultation and reduced peak expiratory flow rate. Diagnosis is typically made through spirometry, which measures the volume and speed of air during exhalation and inhalation.

      Management of asthma typically involves the use of inhalers to deliver drug therapy directly to the airways. Short-acting beta-agonists such as salbutamol are the first-line treatment for relieving symptoms, while inhaled corticosteroids like beclometasone dipropionate and fluticasone propionate are used for daily maintenance therapy. Long-acting beta-agonists like salmeterol and leukotriene receptor antagonists like montelukast may also be used in combination with other medications. Maintenance and reliever therapy (MART) is a newer approach that combines ICS and a fast-acting LABA in a single inhaler for both daily maintenance and symptom relief. Recent guidelines recommend offering a leukotriene receptor antagonist instead of a LABA for patients on SABA + ICS whose asthma is not well controlled, and considering MART for those with poorly controlled asthma.

    • This question is part of the following fields:

      • Respiratory System
      0
      Seconds
  • Question 9 - A 7-year-old girl visits her GP due to frequent chest infections and inadequate...

    Incorrect

    • A 7-year-old girl visits her GP due to frequent chest infections and inadequate growth and weight gain. The GP refers her to a paediatric clinic where she undergoes additional tests, including a genetic test to screen for cystic fibrosis by detecting mutations in the CFTR gene. The results reveal a mutation in which a stop codon replaces arginine. What is the term for this type of mutation?

      Your Answer:

      Correct Answer: Nonsense mutation

      Explanation:

      Single base mutations can have various effects on the structure and function of the transcribed protein, potentially leading to pathology such as the inactivation of tumour suppressor genes. However, some amino acid changes may not affect protein function and can be considered neutral.

      When a single base mutation occurs and the resulting codon still codes for the same amino acid, it is known as a silent mutation. This is possible due to the degeneracy of the genetic code. In this case, the protein is still translated without any downstream effects on processing or phenotype.

      On the other hand, a synonymous mutation also does not alter the amino acid, but it can cause changes in downstream processing or phenotype of the gene. Examples of conditions caused by this type of mutation include Phenylketonuria and von Hippel-Lindau disease.

      Types of DNA Mutations

      There are different types of DNA mutations that can occur in an organism’s genetic material. One type is called a silent mutation, which does not change the amino acid sequence of a protein. This type of mutation often occurs in the third position of a codon, where the change in the DNA base does not affect the final amino acid produced.

      Another type of mutation is called a nonsense mutation, which results in the formation of a stop codon. This means that the protein being produced is truncated and may not function properly.

      A missense mutation is a point mutation that changes the amino acid sequence of a protein. This can have significant effects on the protein’s function, as the altered amino acid may not be able to perform its intended role.

      Finally, a frameshift mutation occurs when a number of nucleotides are inserted or deleted from the DNA sequence. This can cause a shift in the reading frame of the DNA, resulting in a completely different amino acid sequence downstream. These mutations can have serious consequences for the organism, as the resulting protein may be non-functional or even harmful.

    • This question is part of the following fields:

      • General Principles
      0
      Seconds
  • Question 10 - A 26-year-old male presents with yellow discoloration of his skin. He reports having...

    Incorrect

    • A 26-year-old male presents with yellow discoloration of his skin. He reports having had the flu for the past week but is otherwise in good health. He vaguely remembers his uncle experiencing similar episodes of yellow skin. What is the probable diagnosis and what is the mode of inheritance for this condition?

      Your Answer:

      Correct Answer: Autosomal recessive

      Explanation:

      Gilbert’s Syndrome is inherited in an autosomal recessive manner. It causes unconjugated hyperbilirubinaemia during periods of stress, such as fasting or infection.

      Gilbert’s syndrome is a genetic disorder that affects the way bilirubin is processed in the body. It is caused by a deficiency of UDP glucuronosyltransferase, which leads to unconjugated hyperbilirubinemia. This means that bilirubin is not properly broken down and eliminated from the body, resulting in jaundice. However, jaundice may only be visible during certain conditions such as fasting, exercise, or illness. The prevalence of Gilbert’s syndrome is around 1-2% in the general population.

      To diagnose Gilbert’s syndrome, doctors may look for a rise in bilirubin levels after prolonged fasting or the administration of IV nicotinic acid. However, treatment is not necessary for this condition. While the exact mode of inheritance is still debated, it is known to be an autosomal recessive disorder.

    • This question is part of the following fields:

      • Gastrointestinal System
      0
      Seconds
  • Question 11 - A 26-year-old female presents to the emergency department with a 2-day history of...

    Incorrect

    • A 26-year-old female presents to the emergency department with a 2-day history of suprapubic pain and fever. She has no significant medical or surgical history but takes a daily combined oral contraceptive pill and multivitamin. The surgical team orders a CT scan of the abdomen and pelvis, which shows pelvic fat stranding and free fluid in the pouch of Douglas. What is the most probable causative organism?

      Your Answer:

      Correct Answer: Chlamydia trachomatis

      Explanation:

      Pelvic inflammatory disease can be a challenging diagnosis for emergency practitioners, as it presents with vague abdominal pain that can be mistaken for a surgical or gynecological issue. While CT scans are not ideal for young patients due to the risk of radiation exposure to the sex organs, they can reveal common findings for pelvic inflammatory disease, such as free fluid in the pouch of Douglas, pelvic fat stranding, tubo-ovarian abscesses, and fallopian tube thickening of more than 5 mm. In contrast, CT scans for appendicitis may show appendiceal dilatation, thickening of the caecal apex with a bar sign, periappendiceal fat stranding and phlegmon, and focal wall nonenhancement in cases of gangrenous appendix. The most common cause of pelvic inflammatory disease is Chlamydia trachomatis, followed by Neisseria gonorrhoeae and Mycobacterium tuberculosis. In cases of appendicitis, Escherichia coli is the most likely causative organism, with rare cases caused by other organisms.

      Pelvic inflammatory disease (PID) is a condition where the female pelvic organs, including the uterus, fallopian tubes, ovaries, and surrounding peritoneum, become infected and inflamed. It is typically caused by an infection that spreads from the endocervix. The most common causative organism is Chlamydia trachomatis, followed by Neisseria gonorrhoeae, Mycoplasma genitalium, and Mycoplasma hominis. Symptoms of PID include lower abdominal pain, fever, dyspareunia, dysuria, menstrual irregularities, vaginal or cervical discharge, and cervical excitation.

      To diagnose PID, a pregnancy test should be done to rule out an ectopic pregnancy, and a high vaginal swab should be taken to screen for Chlamydia and gonorrhoeae. However, these tests may often be negative, so consensus guidelines recommend having a low threshold for treatment due to the potential complications of untreated PID. Management typically involves oral ofloxacin and oral metronidazole or intramuscular ceftriaxone, oral doxycycline, and oral metronidazole. In mild cases of PID, intrauterine contraceptive devices may be left in, but the evidence is limited, and removal of the IUD may be associated with better short-term clinical outcomes according to recent guidelines.

      Complications of PID include perihepatitis (Fitz-Hugh Curtis Syndrome), which occurs in around 10% of cases and is characterized by right upper quadrant pain that may be confused with cholecystitis, infertility (with a risk as high as 10-20% after a single episode), chronic pelvic pain, and ectopic pregnancy.

    • This question is part of the following fields:

      • Reproductive System
      0
      Seconds
  • Question 12 - A 50-year-old man presents to his GP with complaints of weight loss and...

    Incorrect

    • A 50-year-old man presents to his GP with complaints of weight loss and night sweats. He reports feeling fatigued more easily than usual. During the physical examination, the doctor observes significant splenomegaly. The patient's lab results show an elevated white blood cell count and a translocation between two chromosomes. Which two chromosomes are likely to be translocated in this case?

      Your Answer:

      Correct Answer: (9;22)

      Explanation:

      Based on his symptoms of night sweats, weight loss, fatigue, and splenomegaly, the patient is likely suffering from chronic myelogenous leukemia (CML). This type of leukemia is characterized by a specific translocation between chromosome 9 and 22, known as the Philadelphia chromosome. Other translocations are associated with different types of blood cancers, such as t(15;17) in acute promyelocytic leukemia, t(8;14) in Burkitt’s lymphoma, and t(11;14) in mantle cell lymphoma.

      Genetics of Haematological Malignancies

      Haematological malignancies are cancers that affect the blood, bone marrow, and lymphatic system. These cancers are often associated with specific genetic abnormalities, such as translocations. Here are some common translocations and their associated haematological malignancies:

      – Philadelphia chromosome (t(9;22)): This translocation is present in more than 95% of patients with chronic myeloid leukaemia (CML). It results in the fusion of the Abelson proto-oncogene with the BCR gene on chromosome 22, creating the BCR-ABL gene. This gene codes for a fusion protein with excessive tyrosine kinase activity, which is a poor prognostic indicator in acute lymphoblastic leukaemia (ALL).

      – t(15;17): This translocation is seen in acute promyelocytic leukaemia (M3) and involves the fusion of the PML and RAR-alpha genes.

      – t(8;14): Burkitt’s lymphoma is associated with this translocation, which involves the translocation of the MYC oncogene to an immunoglobulin gene.

      – t(11;14): Mantle cell lymphoma is associated with the deregulation of the cyclin D1 (BCL-1) gene.

      – t(14;18): Follicular lymphoma is associated with increased BCL-2 transcription due to this translocation.

      Understanding the genetic abnormalities associated with haematological malignancies is important for diagnosis, prognosis, and treatment.

    • This question is part of the following fields:

      • Haematology And Oncology
      0
      Seconds
  • Question 13 - Lauren formulates a null hypothesis that taking aspirin every day decreases the risk...

    Incorrect

    • Lauren formulates a null hypothesis that taking aspirin every day decreases the risk of a heart attack in individuals over the age of 50. When testing this hypothesis, she wants to determine the likelihood of avoiding a type II error.

      What is the term used to describe this probability and how can it be improved?

      Your Answer:

      Correct Answer: Power - increasing the sample size

      Explanation:

      Power refers to the likelihood of correctly rejecting the null hypothesis when it is false, which is also the probability of avoiding a type II error. In contrast, a type II error occurs when the null hypothesis is accepted despite being false, resulting in a false negative. The sample size, or the number of subjects analyzed, plays a crucial role in determining power. Increasing the sample size leads to more precise results and a higher probability of correctly rejecting the null hypothesis, while decreasing the sample size results in less accurate results and a lower power. It is important to note that a type I error refers to rejecting the null hypothesis when it is actually true, while a type III error is not a recognized term in statistics.

      Significance tests are used to determine the likelihood of a null hypothesis being true. The null hypothesis states that two treatments are equally effective, while the alternative hypothesis suggests that there is a difference between the two treatments. The p value is the probability of obtaining a result by chance that is at least as extreme as the observed result, assuming the null hypothesis is true. Two types of errors can occur during significance testing: type I, where the null hypothesis is rejected when it is true, and type II, where the null hypothesis is accepted when it is false. The power of a study is the probability of correctly rejecting the null hypothesis when it is false, and it can be increased by increasing the sample size.

    • This question is part of the following fields:

      • General Principles
      0
      Seconds
  • Question 14 - What function does high density lipoprotein (HDL) serve? ...

    Incorrect

    • What function does high density lipoprotein (HDL) serve?

      Your Answer:

      Correct Answer: To move lipids from the arterial walls to the liver

      Explanation:

      The Role of HDL in Reverse Cholesterol Transport

      HDL, also known as good cholesterol, is initially secreted by the liver into the bloodstream as immature or nascent HDL. This nascent HDL contains apoplipoprotein A-I, C, and E but has very little triglyceride or cholesterol ester content. However, upon secretion, it undergoes modification to form the mature form of HDL.

      The mature HDL particle plays a crucial role in reverse cholesterol transport. It receives triglycerides and cholesterol esters from VLDL and IDL particles and picks up excess cholesterol from body cells. As it does so, it loses apoC and E to form the mature HDL particle, which contains only apoA-I.

      The primary function of HDL is to remove excess triglycerides from arterial walls and body cells via VLDL and IDL and to return the excess lipid to the liver for repackaging or excretion in bile. This process is known as reverse cholesterol transport and is essential in maintaining healthy cholesterol levels in the body.

    • This question is part of the following fields:

      • Clinical Sciences
      0
      Seconds
  • Question 15 - A 16-year-old girl comes to the doctor with a cellulitic infection in her...

    Incorrect

    • A 16-year-old girl comes to the doctor with a cellulitic infection in her leg. The infection was caused by a pathogen that triggered an immune response from T cells. Where did the T cells develop?

      Your Answer:

      Correct Answer: Thymus

      Explanation:

      The bone marrow sends T cells to the thymus, where they mature in organized zones within multi-lobar structures. During thymic education, they acquire a functional TCR and express either CD4 or CD8 molecules.

      Cell Surface Proteins and Their Functions

      Cell surface proteins play a crucial role in identifying and distinguishing different types of cells. The table above lists the most common cell surface markers associated with particular cell types, such as CD34 for haematopoietic stem cells and CD19 for B cells. Meanwhile, the table below describes the major clusters of differentiation (CD) molecules and their functions. For instance, CD3 is the signalling component of the T cell receptor (TCR) complex, while CD4 is a co-receptor for MHC class II and is used by HIV to enter T cells. CD56, on the other hand, is a unique marker for natural killer cells, while CD95 acts as the FAS receptor and is involved in apoptosis.

      Understanding the functions of these cell surface proteins is crucial in various fields, such as immunology and cancer research. By identifying and targeting specific cell surface markers, researchers can develop more effective treatments for diseases and disorders.

    • This question is part of the following fields:

      • General Principles
      0
      Seconds
  • Question 16 - A teenage girl is hospitalized with E-coli 0157 following a trip to Germany...

    Incorrect

    • A teenage girl is hospitalized with E-coli 0157 following a trip to Germany during an outbreak. What statement about the condition is false?

      Your Answer:

      Correct Answer: Adults typically develop haemolytic uraemic syndome.

      Explanation:

      This complication is typically developed by children.

      Gastroenteritis can occur either at home or while traveling abroad, which is known as travelers’ diarrhea. This type of diarrhea is characterized by at least three loose to watery stools in 24 hours, along with abdominal cramps, fever, nausea, vomiting, or blood in the stool. The most common cause of travelers’ diarrhea is Escherichia coli. Another type of illness is acute food poisoning, which is caused by the ingestion of a toxin and results in sudden onset of nausea, vomiting, and diarrhea. Staphylococcus aureus, Bacillus cereus, and Clostridium perfringens are the typical causes of acute food poisoning.

      Different infections have stereotypical histories and presentations. Escherichia coli is common among travelers and causes watery stools, abdominal cramps, and nausea. Giardiasis results in prolonged, non-bloody diarrhea. Cholera causes profuse, watery diarrhea and severe dehydration resulting in weight loss, but it is not common among travelers. Shigella causes bloody diarrhea, vomiting, and abdominal pain. Staphylococcus aureus causes severe vomiting with a short incubation period. Campylobacter usually starts with a flu-like prodrome and is followed by crampy abdominal pains, fever, and diarrhea, which may be bloody and may mimic appendicitis. Bacillus cereus has two types of illness: vomiting within six hours, typically due to rice, and diarrheal illness occurring after six hours. Amoebiasis has a gradual onset of bloody diarrhea, abdominal pain, and tenderness that may last for several weeks.

      The incubation period for different infections varies. Staphylococcus aureus and Bacillus cereus have an incubation period of 1-6 hours, while Salmonella and Escherichia coli have an incubation period of 12-48 hours. Shigella and Campylobacter have an incubation period of 48-72 hours, while Giardiasis and Amoebiasis have an incubation period of more than seven days. The vomiting subtype of Bacillus cereus has an incubation period of 6-14 hours, while the diarrheal illness has an incubation period of more than six hours.

    • This question is part of the following fields:

      • General Principles
      0
      Seconds
  • Question 17 - Which one of the following is not a pathological response to extensive burns...

    Incorrect

    • Which one of the following is not a pathological response to extensive burns in elderly patients?

      Your Answer:

      Correct Answer: Absolute polycythaemia

      Explanation:

      The primary pathological response is haemolysis.

      Pathology of Burns

      Extensive burns can cause various pathological changes in the body. The heat and microangiopathy can damage erythrocytes, leading to haemolysis. The loss of capillary membrane integrity can cause plasma leakage into the interstitial space, resulting in hypovolaemic shock. This shock can occur up to 48 hours after the injury and can cause a decrease in blood volume and an increase in haematocrit. Additionally, protein loss and secondary infections, such as Staphylococcus aureus, can occur. There is also a risk of acute peptic stress ulcers, known as Curling’s ulcers. Furthermore, full-thickness circumferential burns in an extremity can lead to compartment syndrome.

      The healing process of burns depends on the severity of the burn. Superficial burns can heal through the migration of keratinocytes to form a new layer over the burn site. However, full-thickness burns can result in dermal scarring, which may require skin grafts to provide optimal coverage. It is important to understand the pathology of burns to provide appropriate treatment and prevent further complications.

    • This question is part of the following fields:

      • Musculoskeletal System And Skin
      0
      Seconds
  • Question 18 - A 45-year-old obese woman presents to the Emergency Department complaining of sudden lower...

    Incorrect

    • A 45-year-old obese woman presents to the Emergency Department complaining of sudden lower back pain. Upon conducting a neurological examination, you observe a decrease in the left knee jerk reflex compared to the right. Which spinal level does this correspond to?

      Your Answer:

      Correct Answer: L3-L4

      Explanation:

      Memory aid for common reflexes:
      S1-S2, buckle my shoe (ankle)
      L3-L4, kick the door (knee)
      C5-C6, pick up sticks (biceps)
      C7-C8, shut the gate (triceps)

      The reflex tested by tapping the knee is the L3-L4 reflex.

      Reflexes are automatic responses that our body makes in response to certain stimuli. These responses are controlled by the nervous system and do not require conscious thought. There are several common reflexes that are associated with specific roots in the spinal cord. For example, the ankle reflex is associated with the S1-S2 root, while the knee reflex is associated with the L3-L4 root. Similarly, the biceps reflex is associated with the C5-C6 root, and the triceps reflex is associated with the C7-C8 root. Understanding these reflexes can help healthcare professionals diagnose and treat certain conditions.

    • This question is part of the following fields:

      • Neurological System
      0
      Seconds
  • Question 19 - A new test for heart disease has a specificity of 95% and a...

    Incorrect

    • A new test for heart disease has a specificity of 95% and a sensitivity of 98%. A thousand people under the age of 50 undergo the new test.

      How many of these individuals will test negative?

      Your Answer:

      Correct Answer: 950

      Explanation:

      Precision refers to the consistency of a test in producing the same results when repeated multiple times. It is an important aspect of test reliability and can impact the accuracy of the results. In order to assess precision, multiple tests are performed on the same sample and the results are compared. A test with high precision will produce similar results each time it is performed, while a test with low precision will produce inconsistent results. It is important to consider precision when interpreting test results and making clinical decisions.

    • This question is part of the following fields:

      • General Principles
      0
      Seconds
  • Question 20 - A 33-year-old man arrives at the emergency department with symptoms of increased thirst...

    Incorrect

    • A 33-year-old man arrives at the emergency department with symptoms of increased thirst and frequent urination. He had suffered a head injury a few days ago and had previously been discharged after investigations. Upon examination, he appears dehydrated and is admitted to a medical ward. The urine osmolality test results show a low level of 250 mosmol/kg after water deprivation and a high level of 655 mosmol/kg after desmopressin administration. Based on this information, where is the deficient substance typically active?

      Your Answer:

      Correct Answer: Collecting duct

      Explanation:

      The site of action for antidiuretic hormone (ADH) is the collecting ducts in the kidneys. A diagnosis of cranial diabetes insipidus, which can occur after head trauma, is confirmed by low urine osmolalities. In this condition, there is a deficiency of ADH, which is synthesized in the hypothalamus but acts on the collecting ducts to promote water reabsorption. Therefore, the hypothalamus is not the site of action for ADH, despite being where it is synthesized. The Loop of Henle and proximal convoluted tubule are also not the primary sites of action for ADH. ADH is released from the posterior pituitary gland, but its action occurs in the collecting ducts.

      Understanding Antidiuretic Hormone (ADH)

      Antidiuretic hormone (ADH) is a hormone that is produced in the supraoptic nuclei of the hypothalamus and released by the posterior pituitary gland. Its primary function is to conserve body water by promoting water reabsorption in the collecting ducts of the kidneys through the insertion of aquaporin-2 channels.

      ADH secretion is regulated by various factors. An increase in extracellular fluid osmolality, a decrease in volume or pressure, and the presence of angiotensin II can all increase ADH secretion. Conversely, a decrease in extracellular fluid osmolality, an increase in volume, a decrease in temperature, or the absence of ADH can decrease its secretion.

      Diabetes insipidus (DI) is a condition that occurs when there is either a deficiency of ADH (cranial DI) or an insensitivity to ADH (nephrogenic DI). Cranial DI can be treated with desmopressin, which is an analog of ADH.

      Overall, understanding the role of ADH in regulating water balance in the body is crucial for maintaining proper hydration and preventing conditions like DI.

    • This question is part of the following fields:

      • Endocrine System
      0
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Endocrine System (0/1) 0%
Gastrointestinal System (0/1) 0%
Passmed