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  • Question 1 - A 60-year-old man is experiencing bone pain and declining kidney function. Bence-Jones proteins...

    Incorrect

    • A 60-year-old man is experiencing bone pain and declining kidney function. Bence-Jones proteins have been detected in his urine and a whole-body MRI has shown osteolytic lesions. To confirm the diagnosis, his physician orders a bone marrow aspiration.

      Which cells are being sought in the bone marrow examination?

      Your Answer: Reed-Sternberg cells

      Correct Answer: B-cells

      Explanation:

      Plasma cells would be visible in a bone marrow aspirate to diagnose multiple myeloma, which is characterized by osteolytic lesions, decreased renal function, bony pain, and the presence of Bence-Jones proteins. This condition is a type of B-cell neoplasm affecting plasma cells.

      Understanding Multiple Myeloma: Features and Investigations

      Multiple myeloma is a type of cancer that affects the plasma cells in the bone marrow. It is most commonly found in patients aged 60-70 years. The disease is characterized by a range of symptoms, which can be remembered using the mnemonic CRABBI. These include hypercalcemia, renal damage, anemia, bleeding, bone lesions, and increased susceptibility to infection. Other features of multiple myeloma include amyloidosis, carpal tunnel syndrome, neuropathy, and hyperviscosity.

      To diagnose multiple myeloma, a range of investigations are required. Blood tests can reveal anemia, renal failure, and hypercalcemia. Protein electrophoresis can detect raised levels of monoclonal IgA/IgG proteins in the serum, while bone marrow aspiration can confirm the diagnosis if the number of plasma cells is significantly raised. Imaging studies, such as whole-body MRI or X-rays, can be used to detect osteolytic lesions.

      The diagnostic criteria for multiple myeloma require one major and one minor criteria or three minor criteria in an individual who has signs or symptoms of the disease. Major criteria include the presence of plasmacytoma, 30% plasma cells in a bone marrow sample, or elevated levels of M protein in the blood or urine. Minor criteria include 10% to 30% plasma cells in a bone marrow sample, minor elevations in the level of M protein in the blood or urine, osteolytic lesions, or low levels of antibodies in the blood. Understanding the features and investigations of multiple myeloma is crucial for early detection and effective treatment.

    • This question is part of the following fields:

      • Haematology And Oncology
      29.2
      Seconds
  • Question 2 - A 63-year-old man presents with a 5-month history of non-specific back pain, fatigue...

    Correct

    • A 63-year-old man presents with a 5-month history of non-specific back pain, fatigue and loss of appetite. He has a medical history of type 2 diabetes mellitus controlled with diet, chronic obstructive pulmonary disease, and seasonal affective disorder. He has a 30 pack-year smoking history. On examination, his vital signs are within normal limits except for saturations of 94% on room air. A chest x-ray shows hyperinflated lung fields bilaterally, unchanged from a previous x-ray. Blood tests and urine analysis reveal a positive urinary Bence-Jones protein. Based on these findings, what is the most likely diagnosis?

      Your Answer: Multiple myeloma

      Explanation:

      The diagnosis of multiple myeloma can be supported by the presence of Bence-Jones protein on urinary analysis, although it is not always necessary. This haematological malignancy of plasma cells is characterized by bone pain and lytic bone lesions. Hypercalcaemia can also indicate the presence of multiple myeloma.

      Ankylosing spondylitis is a chronic inflammatory arthritis that typically affects young men and is associated with HLA-B27. Symptoms include early-morning back pain that improves with exercise, and an elevated ESR may be observed.

      Chronic myeloid leukaemia (CML) is a haematological malignancy that is linked to genetic translocation on chromosome 9 (Philadelphia chromosome). It is characterized by high white cell count, splenomegaly, and blast cells seen on marrow biopsy.

      Gastric and pancreatic cancer may present with non-specific symptoms such as fatigue, weight loss, loss of appetite, and abdominal fullness or pain. Biochemistry may be normal or show raised inflammatory markers, and diagnosis is confirmed through biopsy following imaging.

      Understanding Multiple Myeloma: Features and Investigations

      Multiple myeloma is a type of cancer that affects the plasma cells in the bone marrow. It is most commonly found in patients aged 60-70 years. The disease is characterized by a range of symptoms, which can be remembered using the mnemonic CRABBI. These include hypercalcemia, renal damage, anemia, bleeding, bone lesions, and increased susceptibility to infection. Other features of multiple myeloma include amyloidosis, carpal tunnel syndrome, neuropathy, and hyperviscosity.

      To diagnose multiple myeloma, a range of investigations are required. Blood tests can reveal anemia, renal failure, and hypercalcemia. Protein electrophoresis can detect raised levels of monoclonal IgA/IgG proteins in the serum, while bone marrow aspiration can confirm the diagnosis if the number of plasma cells is significantly raised. Imaging studies, such as whole-body MRI or X-rays, can be used to detect osteolytic lesions.

      The diagnostic criteria for multiple myeloma require one major and one minor criteria or three minor criteria in an individual who has signs or symptoms of the disease. Major criteria include the presence of plasmacytoma, 30% plasma cells in a bone marrow sample, or elevated levels of M protein in the blood or urine. Minor criteria include 10% to 30% plasma cells in a bone marrow sample, minor elevations in the level of M protein in the blood or urine, osteolytic lesions, or low levels of antibodies in the blood. Understanding the features and investigations of multiple myeloma is crucial for early detection and effective treatment.

    • This question is part of the following fields:

      • Haematology And Oncology
      41
      Seconds
  • Question 3 - A 26-year-old woman confides in you that she cannot leave her house without...

    Incorrect

    • A 26-year-old woman confides in you that she cannot leave her house without first performing a specific ritual of sanitizing her door handle and washing her hands before and after leaving. She admits that if she deviates from this routine, she becomes extremely anxious and tense. This behavior has been ongoing for two years and is causing her significant distress.

      What is the recommended course of treatment for this probable diagnosis?

      Your Answer: Dialectical behaviour therapy (DBT)

      Correct Answer: Exposure-response prevention (ERP) therapy

      Explanation:

      Understanding Obsessive-Compulsive Disorder

      Obsessive-compulsive disorder (OCD) is a mental health condition that affects 1 to 2% of the population. It is characterized by the presence of obsessions, which are unwanted intrusive thoughts, images, or urges, and compulsions, which are repetitive behaviors or mental acts that a person feels driven to perform. OCD can cause significant functional impairment and distress.

      The causes of OCD are multifactorial, with possible factors including genetics, psychological trauma, and pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections (PANDAS). OCD is also associated with other mental health conditions such as depression, schizophrenia, Sydenham’s chorea, Tourette’s syndrome, and anorexia nervosa.

      Treatment for OCD depends on the level of functional impairment. For mild impairment, low-intensity psychological treatments such as cognitive behavioral therapy (CBT) including exposure and response prevention (ERP) may be sufficient. If this is not effective or the patient cannot engage in psychological therapy, a course of an SSRI or more intensive CBT (including ERP) may be offered. For moderate impairment, a choice of either an SSRI or more intensive CBT (including ERP) may be offered. For severe impairment, combined treatment with an SSRI and CBT (including ERP) may be necessary.

      ERP is a psychological method that involves exposing a patient to an anxiety-provoking situation and then stopping them from engaging in their usual safety behavior. This helps them confront their anxiety, and the habituation leads to the eventual extinction of the response. If treatment with an SSRI is effective, it should be continued for at least 12 months to prevent relapse and allow time for improvement. If an SSRI is ineffective or not tolerated, another SSRI may be tried.

    • This question is part of the following fields:

      • Psychiatry
      32.9
      Seconds
  • Question 4 - During your placement on a gastro ward, a patient in their late 60s...

    Incorrect

    • During your placement on a gastro ward, a patient in their late 60s develops excessive diarrhea. Can you identify the location in the gastrointestinal tract where most of the water is absorbed?

      Your Answer: Colon

      Correct Answer: Jejunum

      Explanation:

      The absorption of water in the gastrointestinal tract is facilitated by the absorption of ions across cell membranes. The majority of water is absorbed in the small intestine, particularly in the jejunum.

      Water Absorption in the Human Body

      Water absorption in the human body is a crucial process that occurs in the small bowel and colon. On average, a person ingests up to 2000ml of liquid orally within a 24-hour period. Additionally, gastrointestinal secretions contribute to a further 8000ml of fluid entering the small bowel. The process of intestinal water absorption is passive and is dependent on the solute load. In the jejunum, the active absorption of glucose and amino acids creates a concentration gradient that facilitates the flow of water across the membrane. On the other hand, in the ileum, most water is absorbed through facilitated diffusion, which involves the movement of water molecules with sodium ions.

      The colon also plays a significant role in water absorption, with approximately 150ml of water entering it daily. However, the colon can adapt and increase this amount following resection. Overall, water absorption is a complex process that involves various mechanisms and is essential for maintaining proper hydration levels in the body.

    • This question is part of the following fields:

      • Renal System
      10.9
      Seconds
  • Question 5 - Which one of the following structures is not at the level of the...

    Correct

    • Which one of the following structures is not at the level of the infrapyloric plane?

      Your Answer: Cardioesophageal junction

      Explanation:

      The cardioesophageal junction is located at the level of T11, which is a frequently tested anatomical knowledge. The oesophagus spans from the lower border of the cricoid cartilage at C6 to the cardioesophageal junction at T11. It is important to note that in newborns, the oesophagus extends from C4 or C5 to T9.

      Anatomical Planes and Levels in the Human Body

      The human body can be divided into different planes and levels to aid in anatomical study and medical procedures. One such plane is the transpyloric plane, which runs horizontally through the body of L1 and intersects with various organs such as the pylorus of the stomach, left kidney hilum, and duodenojejunal flexure. Another way to identify planes is by using common level landmarks, such as the inferior mesenteric artery at L3 or the formation of the IVC at L5.

      In addition to planes and levels, there are also diaphragm apertures located at specific levels in the body. These include the vena cava at T8, the esophagus at T10, and the aortic hiatus at T12. By understanding these planes, levels, and apertures, medical professionals can better navigate the human body during procedures and accurately diagnose and treat various conditions.

    • This question is part of the following fields:

      • Neurological System
      28.3
      Seconds
  • Question 6 - Which of the following indicates a verbal response score of 1 on the...

    Incorrect

    • Which of the following indicates a verbal response score of 1 on the Glasgow Coma Scale?

      Your Answer: Disoriented response

      Correct Answer: No response

      Explanation:

      The Glasgow coma scale is a widely used tool to assess the severity of brain injuries. It is scored between 3 and 15, with 3 being the worst and 15 the best. The scale comprises three parameters: best eye response, best verbal response, and best motor response. The verbal response is scored from 1 to 5, with 1 indicating no response and 5 indicating orientation.

      A score of 13 or higher on the Glasgow coma scale indicates a mild brain injury, while a score of 9 to 12 indicates a moderate injury. A score of 8 or less indicates a severe brain injury.

    • This question is part of the following fields:

      • Neurological System
      13.3
      Seconds
  • Question 7 - The T wave in a typical electrocardiogram is mainly generated by what mechanisms?...

    Correct

    • The T wave in a typical electrocardiogram is mainly generated by what mechanisms?

      Your Answer: Ventricular repolarization

      Explanation:

      The Glasgow coma scale is a widely used tool to assess the severity of brain injuries. It is scored between 3 and 15, with 3 being the worst and 15 the best. The scale comprises three parameters: best eye response, best verbal response, and best motor response. The verbal response is scored from 1 to 5, with 1 indicating no response and 5 indicating orientation.

      A score of 13 or higher on the Glasgow coma scale indicates a mild brain injury, while a score of 9 to 12 indicates a moderate injury. A score of 8 or less indicates a severe brain injury. Healthcare professionals rely on the Glasgow coma scale to assess the severity of brain injuries and determine appropriate treatment. The score is the sum of the scores as well as the individual elements. For example, a score of 10 might be expressed as GCS10 = E3V4M3.

      Best eye response:
      1- No eye opening
      2- Eye opening to pain
      3- Eye opening to sound
      4- Eyes open spontaneously

      Best verbal response:
      1- No verbal response
      2- Incomprehensible sounds
      3- Inappropriate words
      4- Confused
      5- Orientated

      Best motor response:
      1- No motor response.
      2- Abnormal extension to pain
      3- Abnormal flexion to pain
      4- Withdrawal from pain
      5- Localizing pain
      6- Obeys commands

    • This question is part of the following fields:

      • Cardiovascular System
      9.5
      Seconds
  • Question 8 - Which nerve provides sensation to the skin on the palm side of the...

    Correct

    • Which nerve provides sensation to the skin on the palm side of the thumb?

      Your Answer: Median

      Explanation:

      This region receives cutaneous sensation from the median nerve.

      Anatomy and Function of the Median Nerve

      The median nerve is a nerve that originates from the lateral and medial cords of the brachial plexus. It descends lateral to the brachial artery and passes deep to the bicipital aponeurosis and the median cubital vein at the elbow. The nerve then passes between the two heads of the pronator teres muscle and runs on the deep surface of flexor digitorum superficialis. Near the wrist, it becomes superficial between the tendons of flexor digitorum superficialis and flexor carpi radialis, passing deep to the flexor retinaculum to enter the palm.

      The median nerve has several branches that supply the upper arm, forearm, and hand. These branches include the pronator teres, flexor carpi radialis, palmaris longus, flexor digitorum superficialis, flexor pollicis longus, and palmar cutaneous branch. The nerve also provides motor supply to the lateral two lumbricals, opponens pollicis, abductor pollicis brevis, and flexor pollicis brevis muscles, as well as sensory supply to the palmar aspect of the lateral 2 ½ fingers.

      Damage to the median nerve can occur at the wrist or elbow, resulting in various symptoms such as paralysis and wasting of thenar eminence muscles, weakness of wrist flexion, and sensory loss to the palmar aspect of the fingers. Additionally, damage to the anterior interosseous nerve, a branch of the median nerve, can result in loss of pronation of the forearm and weakness of long flexors of the thumb and index finger. Understanding the anatomy and function of the median nerve is important in diagnosing and treating conditions that affect this nerve.

    • This question is part of the following fields:

      • Neurological System
      5.9
      Seconds
  • Question 9 - A 28-year-old male presents to the emergency department with a complaint of right...

    Incorrect

    • A 28-year-old male presents to the emergency department with a complaint of right arm pain. He reports that the pain started abruptly while lifting weights at the gym and that his arm feels weaker than usual.

      Upon performing an ultrasound of the upper arm, a distal biceps tendon tear is identified.

      Which specific movement is expected to be impacted by this injury?

      Your Answer: Shoulder abduction

      Correct Answer: Supination and elbow flexion

      Explanation:

      The biceps brachii is mainly responsible for supination and elbow flexion. If the tendon associated with this muscle is torn, it can affect these movements.

      External rotation is primarily performed by the infraspinatus and teres minor muscles, not the biceps brachii.

      The teres major muscle, not the biceps brachii, is responsible for internal rotation.

      Pronation is performed by the pronator quadratus and pronator teres muscles, while elbow flexion is performed by the triceps muscle. Therefore, these actions are not associated with the biceps brachii.

      Shoulder abduction involves muscles such as the supraspinatus and deltoid, but it does not involve the biceps brachii.

      Upper limb anatomy is a common topic in examinations, and it is important to know certain facts about the nerves and muscles involved. The musculocutaneous nerve is responsible for elbow flexion and supination, and typically only injured as part of a brachial plexus injury. The axillary nerve controls shoulder abduction and can be damaged in cases of humeral neck fracture or dislocation, resulting in a flattened deltoid. The radial nerve is responsible for extension in the forearm, wrist, fingers, and thumb, and can be damaged in cases of humeral midshaft fracture, resulting in wrist drop. The median nerve controls the LOAF muscles and can be damaged in cases of carpal tunnel syndrome or elbow injury. The ulnar nerve controls wrist flexion and can be damaged in cases of medial epicondyle fracture, resulting in a claw hand. The long thoracic nerve controls the serratus anterior and can be damaged during sports or as a complication of mastectomy, resulting in a winged scapula. The brachial plexus can also be damaged, resulting in Erb-Duchenne palsy or Klumpke injury, which can cause the arm to hang by the side and be internally rotated or associated with Horner’s syndrome, respectively.

    • This question is part of the following fields:

      • Musculoskeletal System And Skin
      19.5
      Seconds
  • Question 10 - A 42-year-old woman experiences repeated episodes of biliary colic. How much bile enters...

    Correct

    • A 42-year-old woman experiences repeated episodes of biliary colic. How much bile enters the duodenum in a day, approximately?

      Your Answer: 500 mL

      Explanation:

      The small bowel receives a daily supply of bile ranging from 500 mL to 1.5 L, with the majority of bile salts being reused through the enterohepatic circulation. The contraction of the gallbladder results in a lumenal pressure of around 25 cm water, which can cause severe pain in cases of biliary colic.

      Bile is a liquid that is produced in the liver at a rate of 500ml to 1500mL per day. It is made up of bile salts, bicarbonate, cholesterol, steroids, and water. The flow of bile is regulated by three factors: hepatic secretion, gallbladder contraction, and sphincter of oddi resistance. Bile salts are absorbed in the terminal ileum and are recycled up to six times a day, with over 90% of all bile salts being recycled.

      There are two types of bile salts: primary and secondary. Primary bile salts include cholate and chenodeoxycholate, while secondary bile salts are formed by bacterial action on primary bile salts and include deoxycholate and lithocholate. Deoxycholate is reabsorbed, while lithocholate is insoluble and excreted.

      Gallstones can form when there is an excess of cholesterol in the bile. Bile salts have a detergent action and form micelles, which have a lipid center that transports fats. However, excessive amounts of cholesterol cannot be transported in this way and will precipitate, resulting in the formation of cholesterol-rich gallstones.

    • This question is part of the following fields:

      • Gastrointestinal System
      8.5
      Seconds
  • Question 11 - A 55-year-old male patient complains of sudden chest pain and is being evaluated...

    Correct

    • A 55-year-old male patient complains of sudden chest pain and is being evaluated for acute coronary syndrome. Upon fasting, his serum cholesterol level was found to be 7.1 mmol/L (<5.2). What is the best initial course of action for managing this patient?

      Your Answer: Statin therapy

      Explanation:

      Statin Therapy for Hypercholesterolemia in Acute Coronary Syndrome

      Hypercholesterolemia is a common condition in patients with acute coronary syndrome. The initial treatment approach for such patients is statin therapy, which includes drugs like simvastatin, atorvastatin, and rosuvastatin. Statins have been proven to reduce mortality in both primary and secondary prevention studies. The target cholesterol concentration for patients with hypercholesterolemia and acute coronary syndrome is less than 5 mmol/L.

      According to NICE guidance, statins should be used more widely in conjunction with a QRISK2 score to stratify risk. This will help prevent cardiovascular disease and improve patient outcomes. The guidance recommends that statins be used in patients with a 10% or greater risk of developing cardiovascular disease within the next 10 years. By using statins in conjunction with risk stratification, healthcare professionals can provide more targeted and effective treatment for patients with hypercholesterolemia and acute coronary syndrome.

    • This question is part of the following fields:

      • Pharmacology
      13.9
      Seconds
  • Question 12 - In which location of the skin are melanocytes predominantly located? ...

    Incorrect

    • In which location of the skin are melanocytes predominantly located?

      Your Answer: Stratum granulosum

      Correct Answer: Stratum basale

      Explanation:

      The Role of Melanocytes in Skin Pigmentation

      Melanocytes are a type of epithelial cell found in the basal layer of the epidermis. Despite their location, they have long cytoplasmic processes that extend into the spaces between keratinocytes. These cells are responsible for producing melanin, which is derived from tyrosine. The melanin is then transported along the cytoplasmic processes and into the keratinocytes in the basal and prickle cell layers. Interestingly, it is the rate of melanin production that determines skin tone, rather than the number of melanocytes present.

      The epidermis is composed of four layers, with the stratum corneum being the most superficial and the stratum basale being the deepest. The stratum corneum is also known as the keratin layer, while the stratum granulosum is referred to as the granular layer. The prickle cell layer is known as the stratum spinosum, and the basal layer is the stratum basale. the role of melanocytes in skin pigmentation is important for the mechanisms behind skin color and how it can vary among individuals.

    • This question is part of the following fields:

      • Histology
      12.9
      Seconds
  • Question 13 - A 78-year-old man is admitted to the care of the elderly ward with...

    Incorrect

    • A 78-year-old man is admitted to the care of the elderly ward with urosepsis and an acute kidney injury stage 2. His medical history includes type 2 diabetes, ischaemic heart disease and prostate cancer.

      Assessing his risk of venous thromboembolism (VTE), you determine that he is at high risk. To prevent VTE, you initiate subcutaneous enoxaparin, a low molecular weight heparin. What is the mechanism of action of this medication?

      Your Answer: Inhibits production of thromboxane A2

      Correct Answer: Activates antithrombin III and forms a complex that inhibits factor Xa

      Explanation:

      The activation of antithrombin III (ATIII) is the mechanism by which low-molecular weight heparins (LMWH) produce an anti-coagulant effect. ATIII is a glycoprotein that inhibits several enzymes involved in the clotting cascade, including thrombin, factor Xa, and factor IXa. All heparins work to enhance the effect of ATIII, but LMWH specifically binds to ATIII and produces a conformational change that accelerates its inhibition of factor Xa.

      In contrast, unfractionated heparin also produces a conformational change in ATIII, but due to its larger size, it can also inhibit other clotting factors such as thrombin, factors IXa, XIa, and XIIa.

      Direct oral anticoagulants such as apixaban and rivaroxaban directly inhibit factor Xa, while dabigatran is a direct thrombin inhibitor. Aspirin, on the other hand, inhibits the production of thromboxane A2 by inhibiting COX-1 and COX-2, resulting in reduced platelet aggregation.

      Heparin is a type of anticoagulant medication that comes in two main forms: unfractionated heparin and low molecular weight heparin (LMWH). Both types work by activating antithrombin III, but unfractionated heparin forms a complex that inhibits thrombin, factors Xa, IXa, XIa, and XIIa, while LMWH only increases the action of antithrombin III on factor Xa. Adverse effects of heparins include bleeding, thrombocytopenia, osteoporosis, and hyperkalemia. LMWH has a lower risk of causing heparin-induced thrombocytopenia (HIT) and osteoporosis compared to unfractionated heparin. HIT is an immune-mediated condition where antibodies form against complexes of platelet factor 4 (PF4) and heparin, leading to platelet activation and a prothrombotic state. Treatment for HIT includes direct thrombin inhibitors or danaparoid. Heparin overdose can be partially reversed by protamine sulfate.

    • This question is part of the following fields:

      • General Principles
      22.6
      Seconds
  • Question 14 - A 67-year-old woman visits her GP after discovering a lump in her groin...

    Incorrect

    • A 67-year-old woman visits her GP after discovering a lump in her groin subsequent to relocating. The patient reports that she can push the lump back in, but it returns when she coughs. During the examination, the GP identifies the lump located superior and medial to the pubic tubercle. The GP reduces the lump, applies pressure to the midpoint of the inguinal ligament, and instructs the patient to cough. The lump reappears, leading the GP to tentatively diagnose the patient with a direct inguinal hernia. Through which anatomical structures will the hernia pass?

      Your Answer: Aponeurosis of internal oblique and superficial ring

      Correct Answer: Transversalis fascia and superficial inguinal ring

      Explanation:

      The correct structures for a direct inguinal hernia to pass through are the transversalis fascia (which forms the posterior wall of the inguinal canal) and the superficial ring. If the hernia were to pass through other structures, such as the deep inguinal ring, it would reappear upon increased intra-abdominal pressure. In contrast, an indirect inguinal hernia enters the canal through the deep inguinal ring and exits at the superficial ring, so it would not reappear if the deep inguinal ring were blocked.

      The inguinal canal is located above the inguinal ligament and measures 4 cm in length. Its superficial ring is situated in front of the pubic tubercle, while the deep ring is found about 1.5-2 cm above the halfway point between the anterior superior iliac spine and the pubic tubercle. The canal is bounded by the external oblique aponeurosis, inguinal ligament, lacunar ligament, internal oblique, transversus abdominis, external ring, and conjoint tendon. In males, the canal contains the spermatic cord and ilioinguinal nerve, while in females, it houses the round ligament of the uterus and ilioinguinal nerve.

      The boundaries of Hesselbach’s triangle, which are frequently tested, are located in the inguinal region. Additionally, the inguinal canal is closely related to the vessels of the lower limb, which should be taken into account when repairing hernial defects in this area.

    • This question is part of the following fields:

      • Gastrointestinal System
      38.3
      Seconds
  • Question 15 - A 65-year-old male comes to the head and neck clinic for his postoperative...

    Correct

    • A 65-year-old male comes to the head and neck clinic for his postoperative check-up following the removal of a tumour from his mouth. He reports experiencing numbness and tingling in the floor of his mouth after the surgery. It is suspected that the sensory nerve to the floor of his mouth may have been affected.

      What is the most probable nerve that has been damaged?

      Your Answer: Lingual nerve

      Explanation:

      The lingual nerve provides sensation to the floor of the mouth, a portion of the tongue, and the gingivae of the mandibular lingual. The mandibular nerve transmits sensory fibers to the submandibular glands, while the greater auricular nerve is responsible for sensation in the parotid gland. The hypoglossal nerve, the twelfth cranial nerve, controls tongue movement, and the facial nerve, the seventh cranial nerve, is responsible for salivation, lacrimation, facial movement, and taste in the anterior two-thirds of the tongue.

      Lingual Nerve: Sensory Nerve to the Tongue and Mouth

      The lingual nerve is a sensory nerve that provides sensation to the mucosa of the presulcal part of the tongue, floor of the mouth, and mandibular lingual gingivae. It arises from the posterior trunk of the mandibular nerve and runs past the tensor veli palatini and lateral pterygoid muscles. At this point, it is joined by the chorda tympani branch of the facial nerve.

      After emerging from the cover of the lateral pterygoid, the lingual nerve proceeds antero-inferiorly, lying on the surface of the medial pterygoid and close to the medial aspect of the mandibular ramus. At the junction of the vertical and horizontal rami of the mandible, it is anterior to the inferior alveolar nerve. The lingual nerve then passes below the mandibular attachment of the superior pharyngeal constrictor and lies on the periosteum of the root of the third molar tooth.

      Finally, the lingual nerve passes medial to the mandibular origin of mylohyoid and then passes forwards on the inferior surface of this muscle. Overall, the lingual nerve plays an important role in providing sensory information to the tongue and mouth.

    • This question is part of the following fields:

      • Neurological System
      29.8
      Seconds
  • Question 16 - A 25-year-old man was in a car accident where two cars collided at...

    Incorrect

    • A 25-year-old man was in a car accident where two cars collided at around 60 miles per hour. After being stabilized, the doctor conducts a secondary survey and finds that the patient's right leg is adducted, flexed, and internally rotated. The diagnosis is a hip dislocation. What type of dislocation is probable and why?

      Your Answer: Anterior dislocation as the acetabulum is shallow anteriorly

      Correct Answer: Posterior dislocation as the iliofemoral ligament is strongest

      Explanation:

      The iliofemoral ligament is the strongest ligament stabilizing the hip joint, making posterior dislocations more common. The deep acetabulum of the hip provides stability and reduces the risk of anterior dislocation. The ischiofemoral ligament is the weakest of the three capsular ligaments and does not play a significant role in hip stability. Therefore, the iliofemoral ligament is the most important factor in preventing hip dislocation.

      Anatomy of the Hip Joint

      The hip joint is formed by the articulation of the head of the femur with the acetabulum of the pelvis. Both of these structures are covered by articular hyaline cartilage. The acetabulum is formed at the junction of the ilium, pubis, and ischium, and is separated by the triradiate cartilage, which is a Y-shaped growth plate. The femoral head is held in place by the acetabular labrum. The normal angle between the femoral head and shaft is 130 degrees.

      There are several ligaments that support the hip joint. The transverse ligament connects the anterior and posterior ends of the articular cartilage, while the head of femur ligament (ligamentum teres) connects the acetabular notch to the fovea. In children, this ligament contains the arterial supply to the head of the femur. There are also extracapsular ligaments, including the iliofemoral ligament, which runs from the anterior iliac spine to the trochanteric line, the pubofemoral ligament, which connects the acetabulum to the lesser trochanter, and the ischiofemoral ligament, which provides posterior support from the ischium to the greater trochanter.

      The blood supply to the hip joint comes from the medial circumflex femoral and lateral circumflex femoral arteries, which are branches of the profunda femoris. The inferior gluteal artery also contributes to the blood supply. These arteries form an anastomosis and travel up the femoral neck to supply the head of the femur.

    • This question is part of the following fields:

      • Musculoskeletal System And Skin
      43.8
      Seconds
  • Question 17 - What is true about dependent variables? ...

    Incorrect

    • What is true about dependent variables?

      Your Answer: They are affected by changes of controlled variables

      Correct Answer: They are affected by changes of independent variables

      Explanation:

      Understanding Variables in Research

      Variables are characteristics, numbers, or quantities that can be measured or counted. They are also known as data items and can vary between data units in a population. Examples of variables include age, sex, income, expenses, and grades. In a typical study, there are three main variables: independent, dependent, and controlled.

      The independent variable is the one that the researcher purposely changes during the investigation. The dependent variable is the one that is observed and changes in response to the independent variable. Controlled variables are those that are not changed during the experiment.

      Dependent variables are affected by independent variables but not by controlled variables. For instance, in a weight loss medication study, the dosage of the medication is the independent variable, while the weight of the participants is the dependent variable. The researcher splits the participants into three groups, with each group receiving a different dosage of the medication. After six months, the participants’ weights are measured.

      Understanding variables is crucial in research as it helps researchers to identify the factors that influence the outcome of their studies. By manipulating the independent variable, researchers can observe how it affects the dependent variable. Controlled variables help to ensure that the results are accurate and reliable.

    • This question is part of the following fields:

      • General Principles
      28.1
      Seconds
  • Question 18 - A 35-year-old man visits the physician's clinic with indications of premature ejaculation, which...

    Incorrect

    • A 35-year-old man visits the physician's clinic with indications of premature ejaculation, which is believed to be caused by hypersensitivity of the reflex arc.

      Can you identify the correct description of this reflex arc?

      Your Answer: Erection is controlled by the somatic nervous system via the pudendal nerve

      Correct Answer: Ejaculation is controlled by the sympathetic nervous system at the L1 level

      Explanation:

      The correct statement is that ejaculation is controlled by the sympathetic nervous system at the L1 level. This is because the preganglionic sympathetic cell bodies responsible for ejaculation are located in the central autonomic region of the T12-L1 segments. It is important to note that erection is controlled by the parasympathetic nervous system at the S2-S4 level, and not by the pudendal nerve, which is responsible for supplying sensation to the penis.

      Anatomy of the Sympathetic Nervous System

      The sympathetic nervous system is responsible for the fight or flight response in the body. The preganglionic efferent neurons of this system are located in the lateral horn of the grey matter of the spinal cord in the thoraco-lumbar regions. These neurons leave the spinal cord at levels T1-L2 and pass to the sympathetic chain. The sympathetic chain lies on the vertebral column and runs from the base of the skull to the coccyx. It is connected to every spinal nerve through lateral branches, which then pass to structures that receive sympathetic innervation at the periphery.

      The sympathetic ganglia are also an important part of this system. The superior cervical ganglion lies anterior to C2 and C3, while the middle cervical ganglion (if present) is located at C6. The stellate ganglion is found anterior to the transverse process of C7 and lies posterior to the subclavian artery, vertebral artery, and cervical pleura. The thoracic ganglia are segmentally arranged, and there are usually four lumbar ganglia.

      Interruption of the head and neck supply of the sympathetic nerves can result in an ipsilateral Horners syndrome. For the treatment of hyperhidrosis, sympathetic denervation can be achieved by removing the second and third thoracic ganglia with their rami. However, removal of T1 is not performed as it can cause a Horners syndrome. In patients with vascular disease of the lower limbs, a lumbar sympathetomy may be performed either radiologically or surgically. The ganglia of L2 and below are disrupted, but if L1 is removed, ejaculation may be compromised, and little additional benefit is conferred as the preganglionic fibres do not arise below L2.

    • This question is part of the following fields:

      • Neurological System
      29.7
      Seconds
  • Question 19 - What is the incorrect pairing in the following options? ...

    Correct

    • What is the incorrect pairing in the following options?

      Your Answer: Termination of dural sac and L4

      Explanation:

      Sorry, your input is not clear. Please provide more information or context for me to understand what you want me to do.

      Anatomical Planes and Levels in the Human Body

      The human body can be divided into different planes and levels to aid in anatomical study and medical procedures. One such plane is the transpyloric plane, which runs horizontally through the body of L1 and intersects with various organs such as the pylorus of the stomach, left kidney hilum, and duodenojejunal flexure. Another way to identify planes is by using common level landmarks, such as the inferior mesenteric artery at L3 or the formation of the IVC at L5.

      In addition to planes and levels, there are also diaphragm apertures located at specific levels in the body. These include the vena cava at T8, the esophagus at T10, and the aortic hiatus at T12. By understanding these planes, levels, and apertures, medical professionals can better navigate the human body during procedures and accurately diagnose and treat various conditions.

    • This question is part of the following fields:

      • Neurological System
      14.6
      Seconds
  • Question 20 - A 45-year-old woman visits her doctor complaining of muscle cramps and fatigue. Upon...

    Incorrect

    • A 45-year-old woman visits her doctor complaining of muscle cramps and fatigue. Upon ruling out any musculoskeletal issues, a blood test is conducted which reveals hyperparathyroidism and low serum phosphate levels. It is suspected that the low phosphate levels are due to the inhibitory effect of parathyroid hormone on renal phosphate reabsorption. Which site in the kidney is most likely affected by parathyroid hormone to cause these blood results?

      Your Answer: Distal convoluted tubule

      Correct Answer: Proximal convoluted tubule

      Explanation:

      The proximal convoluted tubule is responsible for the majority of renal phosphate reabsorption. This occurs through co-transport with sodium and up to two thirds of filtered water. The thin ascending limb of the Loop of Henle is impermeable to water but highly permeable to sodium and chloride, while reabsorption of these ions occurs in the thick ascending limb. Parathyroid hormone is most effective at the proximal convoluted tubule due to its role in regulating phosphate reabsorption.

      The Loop of Henle and its Role in Renal Physiology

      The Loop of Henle is a crucial component of the renal system, located in the juxtamedullary nephrons and running deep into the medulla. Approximately 60 litres of water containing 9000 mmol sodium enters the descending limb of the loop of Henle in 24 hours. The osmolarity of fluid changes and is greatest at the tip of the papilla. The thin ascending limb is impermeable to water, but highly permeable to sodium and chloride ions. This loss means that at the beginning of the thick ascending limb the fluid is hypo osmotic compared with adjacent interstitial fluid. In the thick ascending limb, the reabsorption of sodium and chloride ions occurs by both facilitated and passive diffusion pathways. The loops of Henle are co-located with vasa recta, which have similar solute compositions to the surrounding extracellular fluid, preventing the diffusion and subsequent removal of this hypertonic fluid. The energy-dependent reabsorption of sodium and chloride in the thick ascending limb helps to maintain this osmotic gradient. Overall, the Loop of Henle plays a crucial role in regulating the concentration of solutes in the renal system.

    • This question is part of the following fields:

      • Renal System
      17.2
      Seconds
  • Question 21 - A 35-year-old man presents to your clinic with numerous raised tumour-like growths on...

    Incorrect

    • A 35-year-old man presents to your clinic with numerous raised tumour-like growths on his body and hyperpigmented patches on his back and trunk. He reports experiencing frequent headaches, flushing, and palpitations. Upon genetic analysis, a mutation in the NF1 tumour suppressor gene on chromosome 17 is identified.

      If this man were to have a child with his asymptomatic wife, what is the likelihood that the child would inherit the same condition?

      Your Answer: 25%

      Correct Answer: 50%

      Explanation:

      Autosomal Dominant Inheritance: Characteristics and Complicating Factors

      Autosomal dominant diseases are genetic disorders that are inherited in an autosomal dominant pattern. This means that both homozygotes and heterozygotes manifest the disease, and there is no carrier state. Both males and females can be affected, and only affected individuals can pass on the disease. The disease is passed on to 50% of children, and it normally appears in every generation. The risk remains the same for each successive pregnancy.

      However, there are complicating factors that can affect the inheritance of autosomal dominant diseases. One of these factors is non-penetrance, which refers to the lack of clinical signs and symptoms despite having an abnormal gene. For example, 40% of individuals with otosclerosis may not show any symptoms. Another complicating factor is spontaneous mutation, which occurs when there is a new mutation in one of the gametes. This means that 80% of individuals with achondroplasia have unaffected parents.

      In summary, autosomal dominant inheritance is characterized by certain patterns of inheritance, but there are also complicating factors that can affect the expression of the disease. Understanding these factors is important for genetic counseling and for predicting the risk of passing on the disease to future generations.

    • This question is part of the following fields:

      • General Principles
      20.7
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  • Question 22 - A 50-year-old woman is suspected to have hepatitis B. She presents with jaundice...

    Correct

    • A 50-year-old woman is suspected to have hepatitis B. She presents with jaundice and upper abdominal pain. A liver function test was conducted to assess her liver's synthetic capacity.

      Which characteristic will provide the most precise indication of her condition?

      Your Answer: Prothrombin time

      Explanation:

      Liver enzymes are not reliable indicators of liver function, especially in end-stage cirrhosis. Instead, coagulation and albumin levels are better measures to assess liver function.

      Prothrombin time is a useful indicator because it reflects the liver’s ability to produce the necessary coagulation factors for blood clotting. A high PT suggests that the liver is not functioning properly.

      C-reactive protein (CRP) is not a specific indicator of liver function as it can be elevated in response to any infection in the body.

      Hemoglobin levels are not a reliable indicator of liver function as they can be affected by other factors such as anemia or polycythemia.

      Liver function tests are not accurate in assessing synthetic liver function as they only reflect damage to the liver and its surrounding areas. Additionally, some LFTs can be elevated due to other conditions, not just liver disease. For example, elevated GGT levels in an LFT can indicate damage to the bile ducts, which can be caused by a gallstone blocking the duct.

      Understanding Acute Liver Failure

      Acute liver failure is a condition characterized by the sudden onset of liver dysfunction, which can lead to various complications in the body. The causes of acute liver failure include paracetamol overdose, alcohol, viral hepatitis (usually A or B), and acute fatty liver of pregnancy. The symptoms of acute liver failure include jaundice, raised prothrombin time, hypoalbuminaemia, hepatic encephalopathy, and hepatorenal syndrome. It is important to note that liver function tests may not always accurately reflect the synthetic function of the liver, and it is best to assess the prothrombin time and albumin level to determine the severity of the condition. Understanding acute liver failure is crucial in managing and treating this potentially life-threatening condition.

    • This question is part of the following fields:

      • Gastrointestinal System
      17.6
      Seconds
  • Question 23 - A clinical research group is conducting a study on diabetes epidemiology. As part...

    Incorrect

    • A clinical research group is conducting a study on diabetes epidemiology. As part of the study, researchers are collecting data on the age profile of a sample population in India.

      Among the various data collected, one of the variables was the age of a person. This was divided into four categories: under 18, 18-30, 30-50, and over 50. Respondents were asked to select one of these four options.

      What is this type of variable called?

      Your Answer: Nominal categorical variable

      Correct Answer: Ordinal categorical variable

      Explanation:

      Different Types of Data

      When analyzing data, it is important to understand the different types of variables that can be encountered. One such variable is socio-economic status, which is not a numerical value but can be categorized into four ordinal categories. Ordinal categorical data has a logical order to its categorization, but mathematical functions cannot be performed with the numbers assigned to each category.

      Continuous metric data, on the other hand, can take any value and allows for mathematical functions to be performed. Examples of continuous data include height and weight. Discrete metric data is numerical but only takes certain values, such as the number of children in a family. Nominal categorical data has no hierarchy or gradation, such as blood group or yes/no questions.

      Normal parametric data assumes that variables are normally distributed, but this may not be the case for small sample populations. It is important to note that data can often fall into multiple categories. For example, systolic blood pressure can be considered continuous metric data, but in practice, it is often recorded as integers, making it somewhat like a discrete variable. Additionally, if a cut-off point is used, such as 140 mmHg, the data may become dichotomous and fall into the nominal category. the different types of data is crucial for accurate analysis and interpretation.

    • This question is part of the following fields:

      • Clinical Sciences
      16.6
      Seconds
  • Question 24 - A 79-year-old man visits his doctor complaining of chest pain that occurs during...

    Incorrect

    • A 79-year-old man visits his doctor complaining of chest pain that occurs during physical activity and subsides after rest for the past three months. The doctor diagnoses him with angina and prescribes medications. Due to contraindications, beta blockers and calcium channel blockers are not suitable for this patient, so the doctor starts him on ranolazine. What is the main mechanism of action of ranolazine?

      Your Answer: Reduction of heart rate

      Correct Answer: Inhibition of persistent or late inward sodium current

      Explanation:

      Ranolazine is a medication that works by inhibiting persistent or late sodium current in various voltage-gated sodium channels in heart muscle. This results in a decrease in intracellular calcium levels, which in turn reduces tension in the heart muscle and lowers its oxygen demand.

      Other medications used to treat angina include ivabradine, which inhibits funny channels, trimetazidine, which inhibits fatty acid metabolism, nitrates, which increase nitric oxide, and several drugs that reduce heart rate, such as beta blockers and calcium channel blockers.

      It is important to note that ranolazine is not typically the first medication prescribed for angina. The drug management of angina may vary depending on the individual patient’s needs and medical history.

      Angina pectoris can be managed through lifestyle changes, medication, percutaneous coronary intervention, and surgery. In 2011, NICE released guidelines for the management of stable angina. Medication is an important aspect of treatment, and all patients should receive aspirin and a statin unless there are contraindications. Sublingual glyceryl trinitrate can be used to abort angina attacks. NICE recommends using either a beta-blocker or a calcium channel blocker as first-line treatment, depending on the patient’s comorbidities, contraindications, and preferences. If a calcium channel blocker is used as monotherapy, a rate-limiting one such as verapamil or diltiazem should be used. If used in combination with a beta-blocker, a longer-acting dihydropyridine calcium channel blocker like amlodipine or modified-release nifedipine should be used. Beta-blockers should not be prescribed concurrently with verapamil due to the risk of complete heart block. If initial treatment is ineffective, medication should be increased to the maximum tolerated dose. If a patient is still symptomatic after monotherapy with a beta-blocker, a calcium channel blocker can be added, and vice versa. If a patient cannot tolerate the addition of a calcium channel blocker or a beta-blocker, long-acting nitrate, ivabradine, nicorandil, or ranolazine can be considered. If a patient is taking both a beta-blocker and a calcium-channel blocker, a third drug should only be added while awaiting assessment for PCI or CABG.

      Nitrate tolerance is a common issue for patients who take nitrates, leading to reduced efficacy. NICE advises patients who take standard-release isosorbide mononitrate to use an asymmetric dosing interval to maintain a daily nitrate-free time of 10-14 hours to minimize the development of nitrate tolerance. However, this effect is not seen in patients who take once-daily modified-release isosorbide mononitrate.

    • This question is part of the following fields:

      • Cardiovascular System
      34.7
      Seconds
  • Question 25 - A 78-year-old man is receiving community physiotherapy after a prolonged period of immobility...

    Correct

    • A 78-year-old man is receiving community physiotherapy after a prolonged period of immobility caused by depression. He is experiencing difficulty with hip abduction. Which muscle is primarily responsible for this movement?

      Your Answer: Gluteus medius

      Explanation:

      The correct muscle for hip abduction is the gluteus medius, which has anterior and posterior parts. The anterior part contributes to hip flexion and internal rotation, while the posterior part contributes to hip extension and external rotation. When both parts work together, they abduct the hip. The gluteus maximus primarily functions for hip extension and external rotation, while the hamstrings coordinate flexion and extension of the hip and knee joints but do not contribute to abduction. The iliopsoas primarily functions for hip extension.

      Anatomy of the Hip Joint

      The hip joint is formed by the articulation of the head of the femur with the acetabulum of the pelvis. Both of these structures are covered by articular hyaline cartilage. The acetabulum is formed at the junction of the ilium, pubis, and ischium, and is separated by the triradiate cartilage, which is a Y-shaped growth plate. The femoral head is held in place by the acetabular labrum. The normal angle between the femoral head and shaft is 130 degrees.

      There are several ligaments that support the hip joint. The transverse ligament connects the anterior and posterior ends of the articular cartilage, while the head of femur ligament (ligamentum teres) connects the acetabular notch to the fovea. In children, this ligament contains the arterial supply to the head of the femur. There are also extracapsular ligaments, including the iliofemoral ligament, which runs from the anterior iliac spine to the trochanteric line, the pubofemoral ligament, which connects the acetabulum to the lesser trochanter, and the ischiofemoral ligament, which provides posterior support from the ischium to the greater trochanter.

      The blood supply to the hip joint comes from the medial circumflex femoral and lateral circumflex femoral arteries, which are branches of the profunda femoris. The inferior gluteal artery also contributes to the blood supply. These arteries form an anastomosis and travel up the femoral neck to supply the head of the femur.

    • This question is part of the following fields:

      • Musculoskeletal System And Skin
      20.2
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  • Question 26 - A 70-year-old retired delivery man visits his family physician with a complaint of...

    Correct

    • A 70-year-old retired delivery man visits his family physician with a complaint of knee pain. He reports that the pain is present in both knees and worsens towards the end of the day. The pain usually subsides after resting and in the morning. He has been experiencing knee pain for the past few years and used to take paracetamol, which provided relief. However, the pain has recently intensified, limiting his ability to work. The patient occasionally experiences right hip pain, but it does not bother him much. The patient has a medical history of well-controlled diabetes mellitus, hypertension, and lower back pain. He has a body mass index of 32 kg per m2 and takes metformin, insulin, and candesartan regularly. On examination, there is no redness, swelling, or tenderness over the knees. The physician recommends an X-ray of both knees. What is the most probable X-ray finding?

      Your Answer: Narrowed joint space, subchondral sclerosis, osteophytes

      Explanation:

      The patient’s symptoms are most consistent with osteoarthritis, with no signs of inflammation. Radiographic findings of narrowed joint space and osteophytes support this diagnosis. Other differential diagnoses include rheumatoid arthritis, gout, and pseudogout. The patient’s occupation as a delivery man may have contributed to the development of osteoarthritis. The presence of symptoms and limitations in daily activities should be considered in developing a management plan.

      Comparison of Osteoarthritis and Rheumatoid Arthritis

      Osteoarthritis and rheumatoid arthritis are two types of arthritis that affect the joints. Osteoarthritis is caused by mechanical wear and tear, resulting in the localized loss of cartilage, remodelling of adjacent bone, and associated inflammation. On the other hand, rheumatoid arthritis is an autoimmune disease that affects women more commonly than men and can occur in adults of all ages. It typically affects the MCP and PIP joints, causing bilateral symptoms and systemic upset, while osteoarthritis affects large weight-bearing joints such as the hip and knee, as well as the carpometacarpal joint and DIP and PIP joints, causing unilateral symptoms and no systemic upset.

      The typical history of osteoarthritis involves pain following use, which improves with rest, while rheumatoid arthritis involves morning stiffness that improves with use. X-ray findings for osteoarthritis include loss of joint space, subchondral sclerosis, subchondral cysts, and osteophytes forming at joint margins. For rheumatoid arthritis, X-ray findings include loss of joint space, juxta-articular osteoporosis, periarticular erosions, and subluxation.

      In summary, while both osteoarthritis and rheumatoid arthritis affect the joints, they have different causes, affected joints, symptoms, and X-ray findings. Understanding these differences can help with accurate diagnosis and appropriate treatment.

    • This question is part of the following fields:

      • Musculoskeletal System And Skin
      46.1
      Seconds
  • Question 27 - Ben, an 18-year-old male, attends his follow up shoulder clinic appointment following a...

    Incorrect

    • Ben, an 18-year-old male, attends his follow up shoulder clinic appointment following a traumatic football injury.

      Dr. Patel, the orthopaedic surgeon, carries out a shoulder examination and notes winging of the right scapula.

      Which muscle is impacted?

      Your Answer: Rhomboid major

      Correct Answer: Serratus anterior

      Explanation:

      The serratus anterior muscle is supplied by the long thoracic nerve.

      Muscle Innervation Action
      Accessory nerve Trapezius Upper fibres elevate scapula, middle fibres retract scapula, and lower fibres pull scapula inferiorly
      Axillary nerve Deltoid Major abductor of the arm
      Dorsal scapular nerve Levator scapulae Elevates scapula
      Dorsal scapular nerve Rhomboid major Rotate and retract scapula

      The Long Thoracic Nerve and its Role in Scapular Winging

      The long thoracic nerve is derived from the ventral rami of C5, C6, and C7, which are located close to their emergence from intervertebral foramina. It runs downward and passes either anterior or posterior to the middle scalene muscle before reaching the upper tip of the serratus anterior muscle. From there, it descends on the outer surface of this muscle, giving branches into it.

      One of the most common symptoms of long thoracic nerve injury is scapular winging, which occurs when the serratus anterior muscle is weakened or paralyzed. This can happen due to a variety of reasons, including trauma, surgery, or nerve damage. In addition to long thoracic nerve injury, scapular winging can also be caused by spinal accessory nerve injury (which denervates the trapezius) or a dorsal scapular nerve injury.

      Overall, the long thoracic nerve plays an important role in the function of the serratus anterior muscle and the stability of the scapula. Understanding its anatomy and function can help healthcare professionals diagnose and treat conditions that affect the nerve and its associated muscles.

    • This question is part of the following fields:

      • Neurological System
      15.9
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  • Question 28 - Which of the following medications can lead to hyperkalemia? ...

    Incorrect

    • Which of the following medications can lead to hyperkalemia?

      Your Answer: Salbutamol

      Correct Answer: Heparin

      Explanation:

      Hyperkalaemia can be caused by both unfractionated and low-molecular weight heparin due to their ability to inhibit aldosterone secretion. Salbutamol is a known remedy for hyperkalaemia.

      Hyperkalaemia is a condition where there is an excess of potassium in the blood. The levels of potassium in the plasma are regulated by various factors such as aldosterone, insulin levels, and acid-base balance. When there is metabolic acidosis, hyperkalaemia can occur as hydrogen and potassium ions compete with each other for exchange with sodium ions across cell membranes and in the distal tubule. The ECG changes that can be seen in hyperkalaemia include tall-tented T waves, small P waves, widened QRS leading to a sinusoidal pattern, and asystole.

      There are several causes of hyperkalaemia, including acute kidney injury, drugs such as potassium sparing diuretics, ACE inhibitors, angiotensin 2 receptor blockers, spironolactone, ciclosporin, and heparin, metabolic acidosis, Addison’s disease, rhabdomyolysis, and massive blood transfusion. Foods that are high in potassium include salt substitutes, bananas, oranges, kiwi fruit, avocado, spinach, and tomatoes.

      It is important to note that beta-blockers can interfere with potassium transport into cells and potentially cause hyperkalaemia in renal failure patients. In contrast, beta-agonists such as Salbutamol are sometimes used as emergency treatment. Additionally, both unfractionated and low-molecular weight heparin can cause hyperkalaemia by inhibiting aldosterone secretion.

    • This question is part of the following fields:

      • Renal System
      14.5
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  • Question 29 - Which one of the following cells secretes the majority of tumour necrosis factor?...

    Correct

    • Which one of the following cells secretes the majority of tumour necrosis factor?

      Your Answer: Macrophages

      Explanation:

      Understanding Tumour Necrosis Factor and its Inhibitors

      Tumour necrosis factor (TNF) is a cytokine that plays a crucial role in the immune system. It is mainly secreted by macrophages and has various effects on the immune system, such as activating macrophages and neutrophils, acting as a costimulator for T cell activation, and mediating the body’s response to Gram-negative septicaemia. TNF also has anti-tumour effects and binds to both the p55 and p75 receptor, inducing apoptosis and activating NFkB.

      TNF has endothelial effects, including increased expression of selectins and production of platelet activating factor, IL-1, and prostaglandins. It also promotes the proliferation of fibroblasts and their production of protease and collagenase. TNF inhibitors are used to treat inflammatory conditions such as rheumatoid arthritis and Crohn’s disease. Examples of TNF inhibitors include infliximab, etanercept, adalimumab, and golimumab.

      Infliximab is also used to treat active Crohn’s disease unresponsive to steroids. However, TNF blockers can have adverse effects such as reactivation of latent tuberculosis and demyelination. Understanding TNF and its inhibitors is crucial in the treatment of various inflammatory conditions.

    • This question is part of the following fields:

      • Musculoskeletal System And Skin
      4.8
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  • Question 30 - A 10-year-old girl with a peanut allergy ingests a candy bar containing nuts...

    Incorrect

    • A 10-year-old girl with a peanut allergy ingests a candy bar containing nuts and experiences difficulty breathing. Her mother quickly administers an IM injection to her lateral thigh, resulting in rapid improvement. What is the mechanism of action of the drug used in the injection?

      Your Answer: Through a tyrosine kinase receptor

      Correct Answer: Via G protein-coupled receptors

      Explanation:

      Adrenaline exerts its effects by binding to a G protein-coupled receptor located on the cell membrane. Other types of membrane receptors include ligand-gated ion channels and tyrosine kinase receptors. In contrast, steroid hormones bind to intranuclear receptors and modulate DNA transcription. Second messengers such as inositol triphosphate (IP3) bind to cytoplasmic or intracellular receptors.

      Membrane receptors are proteins located on the surface of cells that receive signals from outside the cell and transmit them inside. There are four main types of membrane receptors: ligand-gated ion channel receptors, tyrosine kinase receptors, guanylate cyclase receptors, and G protein-coupled receptors. Ligand-gated ion channel receptors mediate fast responses and include nicotinic acetylcholine, GABA-A & GABA-C, and glutamate receptors. Tyrosine kinase receptors include receptor tyrosine kinase such as insulin, insulin-like growth factor (IGF), and epidermal growth factor (EGF), and non-receptor tyrosine kinase such as PIGG(L)ET, which stands for Prolactin, Immunomodulators (cytokines IL-2, Il-6, IFN), GH, G-CSF, Erythropoietin, and Thrombopoietin.

      Guanylate cyclase receptors contain intrinsic enzyme activity and include atrial natriuretic factor and brain natriuretic peptide. G protein-coupled receptors generally mediate slow transmission and affect metabolic processes. They are activated by a wide variety of extracellular signals such as peptide hormones, biogenic amines (e.g. adrenaline), lipophilic hormones, and light. These receptors have 7-helix membrane-spanning domains and consist of 3 main subunits: alpha, beta, and gamma. The alpha subunit is linked to GDP. Ligand binding causes conformational changes to the receptor, GDP is phosphorylated to GTP, and the alpha subunit is activated. G proteins are named according to the alpha subunit (Gs, Gi, Gq).

      The mechanism of G protein-coupled receptors varies depending on the type of G protein involved. Gs stimulates adenylate cyclase, which increases cAMP and activates protein kinase A. Gi inhibits adenylate cyclase, which decreases cAMP and inhibits protein kinase A. Gq activates phospholipase C, which splits PIP2 to IP3 and DAG and activates protein kinase C. Examples of G protein-coupled receptors include beta-1 receptors (epinephrine, norepinephrine, dobutamine), beta-2 receptors (epinephrine, salbuterol), H2 receptors (histamine), D1 receptors (dopamine), V2 receptors (vas

    • This question is part of the following fields:

      • General Principles
      22.1
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SESSION STATS - PERFORMANCE PER SPECIALTY

Haematology And Oncology (1/2) 50%
Psychiatry (0/1) 0%
Renal System (0/3) 0%
Neurological System (4/7) 57%
Cardiovascular System (1/2) 50%
Musculoskeletal System And Skin (3/5) 60%
Gastrointestinal System (2/3) 67%
Pharmacology (1/1) 100%
Histology (0/1) 0%
General Principles (0/4) 0%
Clinical Sciences (0/1) 0%
Passmed