Explore topic-wise MCQs in Biology.

This section includes 137 Mcqs, each offering curated multiple-choice questions to sharpen your Biology knowledge and support exam preparation. Choose a topic below to get started.

51.

Erethism is seen in which of the following intoxications

A. Lead
B. Mercury
C. Arsine gas
D. Penicillamine
E. Arsenic
Answer» C. Arsine gas
52.

All of the following are NSAIDs EXCEPT

A. Sulindac
B. Piroxicam
C. Gemfibrozil
D. Ketorolac
E. Diflunisal
Answer» D. Ketorolac
53.

Which of the following has a high extraction ratio

A. Trimethoprim
B. Valproic acid
C. Lignocaine
D. Metronidazole
E. Diazepam
Answer» D. Metronidazole
54.

Drugs which enhance other drug metabolism include all of the following EXCEPT

A. Rifampicin
B. Ketoconazole
C. Phenobarbital
D. Griseofulvin
E. Phenytoin
Answer» C. Phenobarbital
55.

Heparin and protamine used together is an example of

A. Physiologic antagonism
B. Chemical antagonism
C. Partial agonism
D. Irreversible antagonism
E. Agonal agonism
Answer» C. Partial agonism
56.

The half life of a drug with a Vd of 200ml/70kg and clearance of 10 /hr/70kg is

A. 10 hours
B. 14 hours
C. 20 hours
D. 40 hours
E. Indeterminate
Answer» C. 20 hours
57.

What is the largest size spontaneous primary pneumothorax that can be managaed without aspiration or thoracostomy?

A. 10%
B. 15%
C. 20%
D. 30%
E. 35%
Answer» D. 30%
58.

Which bug makes up 50% of hospital acquired pneumonia?

A. pneumococcus
B. staph aureus
C. gm ve bacilli
D. legionella
E. chlamydia psittici
Answer» D. legionella
59.

What if the role of aspiration in traumatic pneumothoraces?

A. there is no role
B. first line management in small pneumathoraces only
C. it should be tried in all pneumathoraces as long as there is no respiratory compromise
D. it can be repeated twice before thoracostomy tube is considered
E. none of the above
Answer» B. first line management in small pneumathoraces only
60.

In which sort of pneumoathorax is aspiration likely to be most successful?

A. traumatic
B. secondary
C. primary
D. iatrogenic
E. equally effective in all of the above
Answer» D. iatrogenic
61.

Whatis the recurrence rate of primary spontaneous pneumathoraces?

A. 10%
B. 20%
C. 30%
D. 40%
E. 50%
Answer» F.
62.

Which of the list below is not the cause of an exudative pleural effusion?

A. viral pneumonia
B. pancreatitis
C. TB
D. Malignancy
E. Nephrotic syndrome
Answer» F.
63.

As a generalization, at what PEFR should someone be admitted?

A. PEFR<25% pretreatment and <40% posttreatment
B. PEFR<10% pretreatment and <20% posttreatment
C. PEFR<40% pretreatment and <60% posttreatment
D. PEFR<50% pretreatment and <70% posttreatment
E. PEFR is of no value in this decision
Answer» B. PEFR<10% pretreatment and <20% posttreatment
64.

Which is not a biochemical feature of transudative pleural effusions?

A. protein<30g/l
B. pleural protein:serum protein <0.5
C. pleural LDH : seurm LDH < 0.6
D. pleural glucose< serum glucose
E. none of the above are biochemical features
Answer» E. none of the above are biochemical features
65.

Which is not a possible cause of haemoptysis?

A. PE
B. Mitral stenosis
C. Pneumonia
D. Aortic stenosis
E. Neoplasm
Answer» E. Neoplasm
66.

Which of the list below is not a cause of a transudative pleural effusion?

A. CCF
B. PE
C. SLE/RA
D. Cirrhosis
E. Nephritic syndrome
Answer» D. Cirrhosis
67.

Which drug/intervention is of no proven benefit in management of acute severe asthma in adults?

A. steroids
B. magnesium
C. steroids
D. CPAP
E. Aminophylline
Answer» F.
68.

Which statement is false about haemoptysis?

A. massive haemoptysis is greater than 600ml in 24 hours
B. a CXR is normal in about 25 % of cases
C. in any four cases, one is likely to be due to nonteuberculous infection, one due to neoplasia, one due to rarer causes and one idiopathic
D. in massive hemoptysis the pt should be nursed bleeding lung up
E. if possible a double lumen tube should be reserved for post brochoscopy as a rigid bronchoscope cannot be passed down it
Answer» E. if possible a double lumen tube should be reserved for post brochoscopy as a rigid bronchoscope cannot be passed down it
69.

Which is FALSE regarding CPAP in acute asthma?

A. it decreases the work of breathing
B. it causes bronchodilation and decreases airway resistance
C. it improves gas exchange if used alone in severe asthma
D. it may be an effective alternative to ETT when maximal pharmacotherapy is used
E. it reduces the cardiovascular impact of changes in pressures caused by asthma
Answer» D. it may be an effective alternative to ETT when maximal pharmacotherapy is used
70.

Which drug/intervention is rarely used acutely in the acute setting of exacerbation of COAD?

A. salbutamol
B. CPAP
C. Aminophylline
D. Steroids
E. Ipratropium
Answer» D. Steroids
71.

Which statement is incorrect regarding the acute management of exacerbation of COAD?

A. support for the widespread use of steroids is limited
B. support for the use of salbutamol combined with ipratropium is limited
C. B agonists are widely used assuming the possiblility of a small reversible component to the airflow obstruction
D. Support for the widespread use of CPAP and BiPAP is minimal
E. Theophylline is rarely used acutely
Answer» E. Theophylline is rarely used acutely
72.

Regarding pulmonary emboli, which statement is correct?

A. a normal Aa gradient excludes a PE
B. a paO2>80 excludes a PE
C. a normal CXR excludes a PE
D. anticoagulation reduces mortality from PE from 30% to 10%
E. all of the above are correct
Answer» E. all of the above are correct
73.

With regards to PE which statement is CORRECT?

A. embolectomy has a better outcome than thrombolysis in massive PE
B. streptokinase is more effective with lower side effects than tPA in massive PE
C. LMWH is probably as effective as unfractionated heparin
D. TOE is sensitive for peripheral emboli
E. Spiral CT angiography is better at detecting peripheral clots than central
Answer» D. TOE is sensitive for peripheral emboli
74.

Concerning toxicity of antibiotics

A. Enamel dysplasia is common with aminoglycosides
B. Grey Baby Syndrome occurs with rifampicin use
C. A disulfiram like reaction can occur with macrolides
D. Haemolytic anaemias can occur with sulphonamide use
E. Nephritis is the most common adverse reaction with isoniazid
Answer» E. Nephritis is the most common adverse reaction with isoniazid
75.

Regarding toxicity of antibiotics

A. Enamel dysplasia is common with aminoglycosides
B. Gray baby syndrome occurs with rifampicin use
C. Haemolytic anaemias can occur with sulphonamide use
D. Nephritis is the most common adverse reaction with isoniazid
E. Disulfiram like reaction can occur with macrolides
Answer» D. Nephritis is the most common adverse reaction with isoniazid
76.

All of the following antibiotics bind to the 50S subunit of the ribosome thereby inhibiting proteinsynthesis EXCEPT

A. Chloramphenicol
B. Erythromycin
C. Linezolid
D. Doxycycline
E. Clindamycin
Answer» E. Clindamycin
77.

Ribosomal resistance occurs with

A. Sulphonamides
B. Penicillin
C. Fluoroquinolones
D. Macrolides
E. Trimethoprim
Answer» E. Trimethoprim
78.

Resistance to B lactams

A. Can be due to an efflux pump
B. Is most commonly due to modification of the target PBPs
C. Does not involve penetration of drug to target PBPs
D. Infers resistance only to penicillinc
E. Can involve up to 5 different B lactamases
Answer» B. Is most commonly due to modification of the target PBPs
79.

Regarding resistance to antibiotics

A. Penicillinases cannot inactivate cephalosporins
B. Macrolides can be inactivated by transferases
C. Mutation of aminoglycoside binding site is its main mechanism of resistance
D. Tetracycline resistance is a marker for multidrug resistance
E. Resistance to antibiotics is rarely plasmid encoded
Answer» D. Tetracycline resistance is a marker for multidrug resistance
80.

Inhalational anaesthetics

A. Enflurane is proconvulsant
B. Isoflurane is the inhalational agent of choice in patients with active IHD
C. Nitrous oxide is a useful adjunct to volatile anaesthetic use in women in the first trimester of pregnancy
D. Halothane has a MAC value of 75% making it less potent than desflurane
E. Desflurane is extensively metabolised via the liver
Answer» B. Isoflurane is the inhalational agent of choice in patients with active IHD
81.

Regarding inhaled anaesthetics

A. They reduce MAP in direct proportion to their alveolar concentration
B. Nitrous oxide has a relatively low MAC
C. Halogenated agents have a lower brain:blood partition coefficient
D. Nitrous oxide causes a decrease in tidal volume and an increase in respiratory rate
E. They decrease the metabolic rate in the brain by decreasing cerebral blood flow
Answer» B. Nitrous oxide has a relatively low MAC
82.

The cephalosporin with the highest activity against gram positive cocci is

A. Cefaclor
B. Cephalothin
C. Cefuroxime
D. Cefepime
E. Cefotaxime
Answer» C. Cefuroxime
83.

Resistance to Penicillin and other lactams is due to

A. Modification of target PBPs
B. Impaired penetration of drug to target PBPs
C. Presence of an efflux pump
D. Inactivation of antibiotics by lactamase
E. All of the above
Answer» F.
84.

Regarding non-depolarising muscle relaxants

A. Pancuronium is eliminated via the kidney
B. Roacuronium is an isoquinolone derivative
C. Roacuronium undergoes Hoffman elimination
D. Vecuronium is eliminated predominantly via the kidney
E. Atracurium is eliminated via plasma pseudocholinesterase
Answer» B. Roacuronium is an isoquinolone derivative
85.

Regarding local anaesthetics (LA)

A. Lignocaine is metabolised in the liver faster than any of the other amide LA
B. Allergies to amide Las are more common than with the ester Las
C. Prilocaine is the most cardiotoxic LA
D. Cocaine is an amide LA which is often used as a drug of abuse
E. The +1/2 of lignocaine may be increased 3-4 fold in a patient with severe liver disease
Answer» F.
86.

Half life of amphotericin B is

A. 2 seconds
B. 20 minutes
C. 2 hours
D. 2 weeks
E. 2 months
Answer» E. 2 months
87.

Which of the following is a second generation cephalosporin?

A. Cefaclor
B. Ceftazidime
C. Cephalexin
D. Cefotaxime
E. Cephalothin
Answer» B. Ceftazidime
88.

Regarding nondepolarising muscle relaxants

A. Jaw and eye muscles are paralysed before the limb and trunk muscles
B. Rocuronium is the most potent nondepolarising skeletal muscle relaxant
C. Atracurium is a steroid derivative
D. Vecuronium blocks cardiac muscarinic receptors, thus inducing moderate increase in heart rate
E. The nondepolarising agents produce a non-surmountable blockade
Answer» B. Rocuronium is the most potent nondepolarising skeletal muscle relaxant
89.

The skeletal muscle relaxant with the longest duration of action is

A. Suxamethonium
B. Mivacurium
C. Pancuronium
D. Rocuronium
E. Vecuronium
Answer» D. Rocuronium
90.

Methyl dopa

A. Lowers the heart rate and cardiac output more than clonidine does
B. Causes reduction in renal vascular resistance
C. Has minimal CNS side effects
D. Has 80% bioavailability
E. Usual therapeutic dose is about 1 2 mg/day
Answer» C. Has minimal CNS side effects
91.

Which of the following DOES NOT increase the susceptibility of a nerve fibre to conduction blockade by a local anaesthetic

A. Small diameter
B. Myelination
C. Location in the periphery of a nerve
D. High firing rate
E. Short action potential duration
Answer» F.
92.

Diuretics

A. Work to lower BP initially by decreasing peripheral vascular resistance
B. Thiazide diuretics are potassium sparing
C. Are effective in lowering Bp by 20 25 mmHg in most patients
D. BP response to thiazides continues to increase at doses greater than usual therapeutic dose.
E. Diuretics may impair glucose tolerance
Answer» F.
93.

Propranolol

A. Is a B1 specific blocker
B. Causes prominent postural hypotension
C. Inhibits the stimulation of renin production by catecholamines
D. Has a half life of 12 hours
E. Has no effect on plasma lipids
Answer» D. Has a half life of 12 hours
94.

A patient complains of post op muscle pain. This is most likely to be due to

A. Suxamethonium
B. Propofol
C. Isoflurane
D. Atracurium
E. Ketamine
Answer» B. Propofol
95.

Hydralazine

A. Dilates veins but not arterioles
B. Is contraindicated in the treatment of preeclampsia
C. Can cause an SLE type syndrome in up to 10 20% of patients
D. Causes orthostatic hypotension in many cases
E. Is extremely useful as a single agent in treatment of hypertension
Answer» D. Causes orthostatic hypotension in many cases
96.

Which of the following drug s metabolism characteristics are bimodally distributed in the population?

A. Sodium nitroprusside
B. Clonidine
C. Minoxidil
D. Hydralazine
E. Phentolamine
Answer» E. Phentolamine
97.

The following drugs when combined with ACE inhibitors may produce troublesome problems EXCEPT

A. Diclofenac
B. Potassium supplements
C. Spironolactone
D. Lithium
E. Theophylline
Answer» F.
98.

The nitrates

A. Have an antianginal effect via vasodilation of arterioles only
B. Serve to increase preload
C. Have a direct effect on cardiac muscle to cause a decrease in anginal symptoms
D. All have high oral bioavailability
E. Are contraindicated in the presence of increased intracranial pressure
Answer» F.
99.

Regarding Calcium channel blockers

A. Calcium channel blockers are not bound to plasma proteins
B. Nifedipine has less vascular potency than verapamil
C. Felodipine has been shown to inhibit insulin release in humans
D. Diltiazem has a plasma half life of 3 4 hours
E. Verapamil has high affinity for cerebral blood vessels thus decreasing vasospasm post subarachnoid haemorrhage
Answer» E. Verapamil has high affinity for cerebral blood vessels thus decreasing vasospasm post subarachnoid haemorrhage
100.

The ACE inhibitors

A. Inhibit peptidyl dipeptidase thus preventing the inactivation of bradykinin
B. Captopril is a prodrug
C. Are to be used with caution in patients with IHD as reflex sympathetic activation occurs secondary to the hypotensive effects of the ACE inhibitors
D. Have no role in treating the normotensive diabetic patients
E. Are useful antihypertensive agents in late pregnancy
Answer» B. Captopril is a prodrug