-
Question 1
Correct
-
Regarding carbon dioxide transport in the blood, which of the following statements is CORRECT:
Your Answer: Deoxygenated haemoglobin acts as a buffer for H+ ions.
Explanation:CO2generated in the tissues and water combine to form carbonic acid which readily dissociates to form HCO3-and H+. The first part of this reaction is very slow in plasma, but is accelerated dramatically by the enzyme carbonic anhydrase present in red blood cells. Bicarbonate is therefore formed preferentially in red cells, from which it freely diffuses down its concentration gradient into plasma where it is transported to the lungs. The red cell membrane is impermeable to H+ions which remain in the cell. To maintain electroneutrality, Cl-ions diffuse into the cell to replace HCO3-, an effect known as the chloride shift. Deoxygenated haemoglobin acts as a buffer for H+, allowing the reaction to continue.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 2
Correct
-
Normal human immunoglobulin is mostly used to protect against which of the following infectious diseases?
Your Answer: Measles and hepatitis A
Explanation:Immune globulin IM is indicated for prophylaxis following exposureto hepatitis A, to prevent or modify measles (rubeola) in a susceptible person exposed fewer than 6 days previously,for susceptible household contacts of measles patients,particularly contacts <1 year and pregnant women without evidence of immunity, and to modify rubella in exposed pregnant women who will not consider a therapeutic abortion.
-
This question is part of the following fields:
- Immunoglobulins And Vaccines
- Pharmacology
-
-
Question 3
Correct
-
Despite taking the oral contraceptive pill, a 29-year-old woman becomes pregnant. During a medication review, you discover that she is epileptic and that her antiepileptic therapy has recently been changed.Which of the following antiepileptics is most likely to impair the oral contraceptive pill's effectiveness?
Your Answer: Carbamazepine
Explanation:The metabolism of ethinyl oestradiol and progestogens has been shown to be increased by enzyme-inducing antiepileptics. The oral contraceptive pill (OCP) is less effective in preventing pregnancy as a result of this increased breakdown.Antiepileptic drugs that induce enzymes include:CarbamazepinePhenytoinPhenobarbitalTopiramateAntiepileptics that do not induce enzymes are unlikely to affect contraception. Non-enzyme-inducing anticonvulsants include the following:ClonazepamGabapentinLevetiracetamPiracetamSodium valproate is a type of valproate that is used toLamotrigine is an antiepileptic drug that does not cause the production of enzymes. It does, however, require special consideration, unlike other non-enzyme-inducing antiepileptics. The OCP does not appear to affect epilepsy directly, but it does appear to lower lamotrigine levels in the blood. This could result in a loss of seizure control and the occurrence of seizures.
-
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
-
-
Question 4
Correct
-
Regarding benzylpenicillin, which of the following statements is CORRECT:
Your Answer: If meningococcal disease is suspected, benzylpenicillin should be given before transfer to hospital.
Explanation:Benzylpenicillin (although inactivated by bacterial beta-lactamases) is effective for many streptococcal (including pneumococcal), gonococcal, and meningococcal infections and also for anthrax, diphtheria, gas gangrene, leptospirosis, and treatment of Lyme disease. If meningococcal disease (meningitis with non-blanching rash or meningococcal septicaemia) is suspected, benzylpenicillin should be given before transfer to hospital, so long as this does not delay the transfer; benzylpenicillin is no longer the drug of first choice for pneumococcal meningitis. Although benzylpenicillin is effective in the treatment of tetanus, metronidazole is preferred. Benzylpenicillin is inactivated by gastric acid and absorption from the gastrointestinal tract is poor and therefore it must be given by injection.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 5
Correct
-
Antidiuretic hormone (ADH) is synthesised by which of the following:
Your Answer: Hypothalamus
Explanation:Antidiuretic hormone is synthesised in the hypothalamus and transported to the posterior pituitary within nerve fibres where it is stored in secretory granules. ADH binds V2 receptors on renal principal cells in the late distal tubule and collecting ducts, raising cAMP levels and causing intracellular vesicles to fuse with the apical membrane. In their membrane these vesicles have water channels called aquaporins, which increase the water permeability allowing greater water reabsorption and concentration of urine. Excess levels of ADH results in syndrome of inappropriate ADH secretion (SIADH) characterised by hyponatremia with concomitant hypo-osmolality and high urine osmolality.
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 6
Correct
-
In the Kaplan-Meier plot, which of the following labels should be applied to the X-axis?
Your Answer: Time in years
Explanation:Kaplan-Meier estimate is one of the best options to be used to measure the fraction of subjects living for a certain amount of time after treatment. In clinical trials or community trials, the effect of an intervention is assessed by measuring the number of subjects survived or saved after that intervention over a period of time. The time starting from a defined point to the occurrence of a given event, for example death, is called as survival time and the analysis of group data as survival analysis. The graph plotted between estimated survival probabilities/estimated survival percentages (on Y axis) and time past after entry into the study (on X axis) consists of horizontal and vertical lines.
-
This question is part of the following fields:
- Evidence Based Medicine
-
-
Question 7
Correct
-
Which of the following clinical features is a feature of a chronic extravascular haemolytic anaemia:
Your Answer: Gallstones
Explanation:Clinical features of haemolytic anaemia include:AnaemiaJaundice (caused by unconjugated bilirubin in plasma, bilirubin is absent from urine)Pigment gallstonesSplenomegalyAnkle ulcersExpansion of marrow with, in children, bone expansion e.g. frontal bossing in beta-thalassaemia majorAplastic crisis caused by parvovirus
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 8
Correct
-
At which vertebral level does the spinal cord normally end in adults?
Your Answer: L1/L2
Explanation:The spinal cord starts at the foramen magnum, where it is continuous with the medulla oblongata, which is the most caudal portion of the brainstem.It then extends inferiorly through the vertebral canal. In adults, it usually ends at the level of the first or second lumbar vertebra.
-
This question is part of the following fields:
- Anatomy
- Head And Neck
-
-
Question 9
Correct
-
In the emergency room, a 28-year-old woman complains of wobbly and slurred speech, is unable to do the heel-shin test, and has nystagmus. The following signs are most likely related to damage to which of the following areas:
Your Answer: Cerebellum
Explanation:Cerebellar injury causes delayed and disorganized motions. When walking, people with cerebellar abnormalities sway and stagger. Damage to the cerebellum can cause asynergia, the inability to judge distance and when to stop, dysmetria, the inability to perform rapid alternating movements or adiadochokinesia, movement tremors, staggering, wide-based walking or ataxic gait, a proclivity to fall, weak muscles or hypotonia, slurred speech or ataxic dysarthria, and abnormal eye movements or nystagmus.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 10
Correct
-
A 30-year-old man suffers from an open femoral shaft fracture after being involved in a road traffic accident. As a consequence of his injury, the nerve that was damaged innervates the popliteus muscle.In which of the following nerves is the popliteus muscle innervated by?
Your Answer: Tibial nerve
Explanation:The popliteus muscle is innervated by the tibial nerve (L4, 5 and S1).
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
SESSION STATS - PERFORMANCE PER SPECIALTY
