-
Question 1
Correct
-
Calculate the stroke volume in an adult male with the following parameters:
Heart rate 70 beats/min
Arterial [O2] 0.24 ml O2/min
Venous [O2] 0.16 ml O2/mi
Whole body O2 consumption 500 ml/min
Pulmonary diastolic pressure 15 mmHg
Pulmonary systolic pressure 25 mmHg
Wedge pressure 5 mmHg.Your Answer: 90 ml
Explanation:Fick’s principle states that, VO2 = (CO × CAO2) – (CO × CVO2) where VO2 = oxygen consumption, CO = cardiac output, CAO2 = oxygen concentration of arterial blood and CVO2 = oxygen concentration of venous blood. Thus, CO = VO2/CAO2– CVO2, CO = 500/0.24–0.16, CO = 500/0.8, CO = 6.25 l/min. Cardiac output is also given by product of stroke volume and heart rate. Thus, stroke volume = cardiac output / heart rate = 6.25/70 × 1000 stroke volume = 90 ml approximately.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 2
Correct
-
A 35-year-old woman is in a comatose state following a traumatic head injury, and is receiving intravenous (IV) antibiotics and IV fluids containing saline and 5% dextrose. A serum biochemistry analysis is performed five days later which shows a low serum potassium level. This is most likely to be due to:
Your Answer: Nothing per oral regimen
Explanation:In this patient the cause for hypokalaemia is insufficient consumption of potassium as she is nil-per mouth with no intravenous supplementation. Parenteral nutrition has been used for comatose patients, although enteral feeding is usually preferable, and less prone to complications.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
-
-
Question 3
Correct
-
A 35 year-old man presents with high grade fever for 7 days after returning from a trip to India. He tested positive for widal test. What is the most likely organism that caused his fever?
Your Answer: Salmonella typhi
Explanation:Typhoid fever is caused by virulent bacteria called Salmonella typhi. Salmonella typhi spread through contaminated food or water and occasionally through direct contact with someone who is infected.
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 4
Correct
-
The majority of gallstones are mainly composed of:
Your Answer: Cholesterol
Explanation:Bile salts are formed out of cholesterol in the liver cells. Occasionally, precipitation of cholesterol occurs resulting into cholesterol stones developing in the gall bladder.
These cholesterol gallstones are the most common type and account for 80% of all gallstones. Another type, accounting for 20% gallstones is pigment stones which are composed of bilirubin and calcium salts. Occasionally, stones of mixed origin are also seen.
-
This question is part of the following fields:
- Gastroenterology
- Physiology
-
-
Question 5
Correct
-
Which of the following will be affected by a lesion in the posterior column-medial lemniscus system?
Your Answer: Fine touch
Explanation:The posterior column–medial lemniscus (PCML) pathway is a sensory pathway that transmits fine touch and conscious proprioceptive information from the body to the brain. As the posterior columns are also known as dorsal columns, the pathway is also called the dorsal column–medial lemniscus system or DCML.
-
This question is part of the following fields:
- Neurology
- Physiology
-
-
Question 6
Correct
-
A 56 year old gentleman, who is a chronic smoker presents to the clinic with dyspnoea. His Chest X-ray shows intercostal space widening with increased blackening bilaterally. What is the most likely finding on his pulmonary function test?
Your Answer: Increased total lung capacity
Explanation:In patients suspected of having chronic obstructive pulmonary disease, pulmonary function testing (PFT) is useful to confirm airway obstruction, to quantify its severity and reversibility, for following disease progression and monitoring response to treatment. These tests include:
FEV1 – volume of air forcefully expired during the first second after a full breath
Forced vital capacity (FVC) – total volume of air expired with maximal force and flow-volume loops. The hallmark of airway obstruction is reduction of FEV1, FVC and the ratio of FEV1/FVC, with a concave pattern in expiratory tracing on the flow-volume loop. FEV1 and forced vital capacity (FVC) are easily measured with office spirometry and are useful to assess the severity of disease. Other parameters include increased total lung capacity, functional residual capacity and residual volume, which can help distinguish chronic obstructive pulmonary disease (COPD) from restrictive pulmonary disease where these values are lower than normal. Along with these, other tests are decreased vital capacity; and decreased diffusing capacity for carbon monoxide (DLCO). DLCO is non-specific and can be low in other disorders that affect the pulmonary vascular bed, such as interstitial lung disease. DLCO is however useful to distinguish COPD from asthma, in which DLCO is normal or elevated.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 7
Correct
-
Endometrial hyperplasia is most likely to be associated with which of the following conditions?
Your Answer: Fibrothecoma
Explanation:A benign tumour arising from the ovarian stroma, fibrothecoma are bilateral in 10% cases. The thecoma component of the tumour can produce oestrogen leading to endometrial hyperplasia. The thecoma is rich in lipid content and is responsible for the yellowish appearance of the tumour. Meig’s syndrome is the presence of fibrothecoma with a right-sided hydrothorax.
-
This question is part of the following fields:
- Pathology
- Women's Health
-
-
Question 8
Correct
-
Which of the following is found to be elevated in a case of hepatocellular carcinoma?
Your Answer: AFP
Explanation:Alpha-fetoprotein (AFP) is a glycoprotein that is normally produced by the yolk sac of the embryo, and then the fetal liver. It is elevated in the new-born and thus, also in the pregnant women. Eventually, it decreases in the first year of life to reach the adult normal value of < 20 ng/ml by 1 year of age. Markedly elevated levels (>500 ng/ml) in a high-risk patient is considered diagnostic for primary hepatocellular carcinoma (HCC). Moreover, due to smaller tumours secreting less quantities of AFP, rising levels can be a better indication. However, not all hepatocellular carcinomas produce AFP. Also, the level of AFP is not a prognostic factor. Populations where hepatitis B and HCC are common (e.g.: sub-Saharan Africans, ethnic Chinese) can see AFP levels as high as 100,000 ng/ml, whereas levels are low (about 3000 ng/ml) in regions with lesser incidences of HCC.
AFP can also be elevated up to 500 ng/ml in conditions like embryonic teratocarcinomas, hepatoblastomas, fulminant hepatitis, hepatic metastases from gastrointestinal tract cancers, some cholangiocarcinomas). Lesser values are seen in acute and chronic hepatitis.
Overall, the sensitivity of AFP value ≥20 ng/ml is 39-64% and the specificity is 76%–91%. Value of 500 ng/ml is considered as the diagnostic cut-off level for HCC.
-
This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
-
-
Question 9
Correct
-
A tumour growing in the posterior mediastinum is found in a 40-year-old man who presented to the out patient clinic with chest pain. Such a tumour is likely to compress the following structure:
Your Answer: Oesophagus
Explanation:The boundaries of the posterior mediastinum are: the superiorly through the sternal angle and T4/5, inferiorly, the diaphragm, anteriorly, by the middle mediastinal structures and posteriorly by the spinal cord. Structures in the posterior mediastinum include the descending thoracic aorta, the azygos system, oesophagus, thoracic duct and lymph nodes. The great vessels and structures at the root of the lung are part of the middle mediastinum. The oesophagus is the only structure in the posterior mediastinum among the choices.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 10
Correct
-
If the blood flow is constant, oxygen extraction by tissues will show the greatest decrease due to which of the following interventions?
Your Answer: Tissue cooling
Explanation:With a constant blood flow to a given tissue bed, there will be an increase in oxygen extraction by the tissue with the following; an increase in tissue metabolism and oxygen requirements: warming (or fever), exercise, catecholamines and thyroxine. With cooling, the demand for oxygen decreases, leading to decreased oxygen extraction.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 11
Correct
-
A brain tumour causing blockage of the hypophyseal portal system is likely to result in an increased secretion of which of the following hormones?
Your Answer: Prolactin
Explanation:The hypophyseal portal system links the hypothalamus and the anterior pituitary. With the help of this system, the anterior pituitary receives releasing and inhibitory hormones from the hypothalamus and regulates the action of other endocrine glands. One of the inhibitory hormones carried by this system is the prolactin-inhibitory hormone. In the absence of this hormone which might occur in case of a blockage of the system, prolactin secretion increases to about three times normal levels.
-
This question is part of the following fields:
- Endocrinology
- Physiology
-
-
Question 12
Correct
-
Which muscle in the neck divides the neck into two large triangles?
Your Answer: Sternocleidomastoid
Explanation:The sternocleidomastoid muscle is an important landmark in the neck as it divides the neck into two; anterior and posterior triangles. These triangles help in the location of the structures of the neck including the carotid artery, head and neck lymph nodes, accessory nerve and the brachial plexus. It originates from the manubrium and medial portion of the clavicle and inserts on the mastoid process of the temporal bone, superior nuchal line. The sternocleidomastoid receives blood supply from the occipital artery and the superior thyroid artery. It is innervated by the accessory nerve (motor) and cervical plexus (sensory).
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 13
Correct
-
Which of the following is a true statement regarding secretion of gastric acid?
Your Answer: Acetylcholine increases gastric acid secretion
Explanation:Gastric acid secretion is increased by acetylcholine, histamine and gastrin, with the help of cAMP as a secondary messenger. They increase H+ and Cl- secretion by increasing the number of H+/K+ ATPase molecules and Cl- channels. In contrast, gastric acid secretion is decreased by somatostatin, epidermal growth factor and prostaglandins.
-
This question is part of the following fields:
- Gastroenterology
- Physiology
-
-
Question 14
Correct
-
After severe injury of the upper limb following an accident. The humerus is injured as well as the nerve which innervates the muscles of the anterior compartment of the arm. Which nerve is injured?
Your Answer: Musculocutaneous
Explanation:The musculoskeletal nerve supplies the muscles of the anterior compartment of the arm including the coracobrachialis, biceps brachii and the greater part of the brachialis. This nerve derives its fibres from the fifth, sixth and seventh cervical nerves and arises from the lateral cord of the brachial plexus. It also provides a branch to the elbow joint.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 15
Correct
-
What is the basic chemical reaction that takes place in the breakdown of complex foodstuffs?
Your Answer: Hydrolysis
Explanation:Breakdown of complex food into simpler compounds is achieved by hydrolysis, with the help of different enzymes specific for different compounds.
-
This question is part of the following fields:
- Gastroenterology
- Physiology
-
-
Question 16
Correct
-
A 30-year-old woman known with Von Willebrand disease (vWD) has to undergo surgery. Which of these complications is most unlikely in this patient?
Your Answer: Hemarthrosis
Explanation:Von Willebrand disease (vWD) is an inherited haemorrhagic disorder characterised by the impairment of primary haemostasis. It is caused by the deficiency or dysfunction of a protein named von Willebrand factor. The most common manifestation due to the condition is abnormal bleeding. Complications include easy bruising, hematomas, epistaxis, menorrhagia, prolonged bleeding and severe haemorrhage. Hemarthrosis is a complication that is more commonly found in haemophilia.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 17
Correct
-
A Monospot test in a 17-year old boy presenting with fever, multiple palpable lymph nodes and mild icterus was positive. His blood investigation is likely to show which of the following?
Your Answer: Atypical lymphocytosis
Explanation:Epstein-Barr virus is the causative agent for infectious mononucleosis leading to presence of atypical lymphocytes in blood. Usually symptomatic in older children and adults, the incubation period is 30-50 days. Symptoms include fatigue, followed by fever, adenopathy and pharyngitis. Fatigue can last for months and is maximum in first few weeks. Fever spikes in the afternoon or early evening, with temperature around 39.5 – 40.5 °C. The ‘typhoidal’ form where fatigue and fever predominate has a low onset and resolution. Pharyngitis resemble that due to streptococcus and can be severe and painful. Lymphadenopathy is bilaterally symmetrical and can involve any nodes, specially the cervical ones. Mild splenomegaly is seen in 50% cases, usually in 2-3rd week. Mild tender hepatomegaly can occur. Less common manifestations include maculopapular eruptions, jaundice, periorbital oedema and palatal enanthema. Diagnostic tests include full blood count and a heterophil antibody test. Morphologically abnormal lymphocytes account for 80% cells and are heterogenous, unlike leukaemia.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 18
Correct
-
A 5-year-old child presents with fever and otalgia. Greenish pustular discharge was seen in his left ear during physical examination. The patient is diagnosed with otitis externa. Which of the following organisms most likely caused the infection?
Your Answer: Pseudomonas aeruginosa
Explanation:P. aeruginosa is a multidrug resistant pathogen recognised for its ubiquity, its advanced antibiotic resistance mechanisms and its association with serious illnesses – especially hospital-acquired infections such as ventilator-associated pneumonia and various septic syndromes. The species name aeruginosa is a Latin word meaning verdigris (copper rust), referring to the blue-green colour of laboratory cultures of the species. This blue-green pigment is a combination of two metabolites of P. aeruginosa, pyocyanin (blue) and pyoverdine (green), which impart the blue-green characteristic colour of cultures.
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 19
Correct
-
The following organs would be expected to lie within the right lower quadrant of the abdomen, assuming that the gastrointestinal tract is rotated normally:
Your Answer: Distal jejunum, caecum, vermiform appendix
Explanation:The abdomen is divided by theoretical anatomic lines into four quadrants. The median plane follows the linea alba and extends from the xiphoid process to the pubic symphysis and splits the abdomen in half. The transumbilical plane is a horizontal line that runs at the level of the umbilicus. This forms the upper right and left quadrants and the lower right and left quadrants. Structures in the right lower quadrant include: caecum, appendix, part of the small intestine, ascending colon, the right half of the female reproductive system, right ureter. Pain in this region is most commonly associated with appendicitis.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 20
Correct
-
Both the arytenoid muscles and the lateral cricoarytenoid muscles perform this action on the glottis:
Your Answer: Adduction
Explanation:Both the arytenoid and the cricoartenoid muscles close the glottis. The lateral cricoarytenoid muscles extend from the lateral cricoid cartilage to the muscular process of the arytenoid cartilage. By rotating the arytenoid cartilages medially, these muscles adduct the vocal cords and thereby close the rima glottidis. The arytenoid muscle adducts or approximates the arytenoid cartilages, and thus closes the aperture of the glottis.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
SESSION STATS - PERFORMANCE PER SPECIALTY
