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.

101.

Which is the most common organism causing community acquired pneumonia?

A. pneumococcus
B. hemophilus influenzi
C. viral
D. gm negatives
E. mycoplasma
Answer» B. hemophilus influenzi
102.

Which of the following calcium channel blockers has the longest plasma half life?

A. Felodipine
B. Diltiazem
C. Amlodipine
D. Nimodipine
E. Verapamil
Answer» D. Nimodipine
103.

which organism causing pneumonia has an increased association with COPD

A. pneumococcus
B. hemophilus influenzi
C. viral
D. gm negatives
E. mycoplasma
Answer» C. viral
104.

Which of the following calcium channel blockers is excreted predominantly in the faeces?

A. Nifedipine
B. Felodipine
C. Diltiazem
D. Nimodipine
E. Verapamil
Answer» D. Nimodipine
105.

The following include major actions of digoxin on cardiac electrical functions EXCEPT

A. Decreased PR interval on ECG
B. Decreased conduction velocity at the AV node
C. Increased automaticity of the atrial muscle
D. Decreased effective refractory period in purkinje system/ventricles
E. Bigeminy can be induced by digoxin
Answer» B. Decreased conduction velocity at the AV node
106.

Which of the following increases the risk of digoxin induced arrhythmias?

A. Hyperkalaemia
B. Hypercalcaemia
C. Hypermagnesaemia
D. Hyperuricaemia
E. Hypernatraemia
Answer» C. Hypermagnesaemia
107.

Digoxin

A. Is poorly lipid soluble
B. Is extensively metabolized
C. Has a half life in the body of 40 hours
D. Has minimal GI toxicity
E. Is 80% bound to plasma proteins
Answer» D. Has minimal GI toxicity
108.

Drugs which may increase digoxin effect include all of the following EXCEPT

A. Amiodarone
B. Diltiazem
C. Frusemide
D. Quinidine
E. Antacids
Answer» F.
109.

Which of the following drugs has the smallest volume of distribution?

A. Chloroquine
B. Verapamil
C. Imipramine
D. Warfarin
E. Digoxin
Answer» E. Digoxin
110.

Which organism causing pneumonia has an increased incidence in IV drug users and those post-influenza?

A. pneumococcus
B. staph aureus
C. viral
D. gm negatives
E. mycoplasma
Answer» C. viral
111.

Which drug/s should be used in adult mild-mod. Community acquired pneumonia?

A. amoxycillin
B. doxycycline
C. rulide
D. any of the above as a single drug
E. amoxycillin and rulide
Answer» E. amoxycillin and rulide
112.

Drugs of abuse can be extremely dangerous in the wrong hands! Which of the following is correct

A. Ketamine is structurally related to psilocybin
B. LSD acts on various 5 HT receptor subtypes to produce its mind altering effects
C. Marijuana causes mydriasis and conjunctival infection
D. Cocaine has a long plasma half life
E. Amphetamine like drugs cause marked stimulation of appetite
Answer» C. Marijuana causes mydriasis and conjunctival infection
113.

Regarding pharmacokinetics of antidepressants

A. Most are highly protein bound
B. Fluoxetine is poorly absorbed
C. Tricyclics are predominantly excreted unchanged in the urine
D. Plasma half lives of antidepressants are mostly less than 10 hours
E. The half life of the older MAOIs is helpful in governing doses
Answer» B. Fluoxetine is poorly absorbed
114.

Pharmacokinetics of doxycycline

A. 20% bound by serum proteins
B. 60-70% absorption after oral administration
C. Absorption is impaired by divalent cations, Al3+, and antacids
D. Widely distributed especially into the CSF
E. Is eliminated via renal mechanisms
Answer» D. Widely distributed especially into the CSF
115.

Regarding the pharmacokinetics of the tetracyclines

A. Tetracyclines are 40 to 80 % bound by serum proteins
B. Absorption is enhanced by coadministration of antacids
C. Tetracyclines cross the blood brain barrier easily
D. Doxycycline is excreted predominantly by the kidney
E. Demeclocyline is a short acting tetracycline drug
Answer» B. Absorption is enhanced by coadministration of antacids
116.

Regarding IV anaesthetic agents

A. Ketamine is the induction agent of choice in a head injured patient
B. Propofol has a slow offset of action
C. Etomidate causes hypotension more commonly than thiopentone
D. Ideal agents for neuroleptanalgesia are fentanyl and droperidol
E. Thiopentone is metabolised at a rate of 40-50% per hour in humans following a single dose
Answer» E. Thiopentone is metabolised at a rate of 40-50% per hour in humans following a single dose
117.

Regarding local anaesthetic agents

A. Lignocaine is also an antiarrhythmic of the Vaughan Williams classification group 1A
B. At normal pH the larger fraction of local anaesthetic in the body fluids will be in the unchanged form
C. Bupivacaine may cause an apparent cyanosis in some patients
D. The duration of action of procaine will be increased in the presence of liver disease
E. Local anaesthetic agents block conduction in small myelinated axons prior to blockade of other axons
Answer» F.
118.

Which of the following local anaesthetic agents is an ester

A. Bupivacaine
B. Ropivacaine
C. Prilocaine
D. Procaine
E. Lignocaine
Answer» E. Lignocaine
119.

Local anaesthetic agents

A. Are primarily K+ channel blockers
B. Prevent repolarisation of the membrane
C. Can be used with a vasodilator to prolong local action
D. Activity is enhanced by high extracellular K+ concentration
E. Activity is enhanced by high extracellular Ca2+
Answer» E. Activity is enhanced by high extracellular Ca2+
120.

Regarding the penicillins

A. Penicillin ix excreted into breast milk to levels 3-15% of those present in the serum
B. Absorption of amoxyl is impaired by food
C. Benzathine penicillin is given PO
D. Penicillins are 90% excreted by glomerular filtration
E. Dosage of nafcillin should be adjusted in the presence of renal failure
Answer» B. Absorption of amoxyl is impaired by food
121.

All of the following are true regarding metronidazole EXCEPT

A. It is used to treat giardia
B. It causes a metallic taste in the mouth
C. It inhibits alcohol dehydrogenase
D. It is used to treat gardnerella
E. It is useful against trichomonoas vaginalis
Answer» D. It is used to treat gardnerella
122.

Regarding temazepam all of the following are true EXCEPT

A. It produces inactive metabolites
B. It induces enzymes only to a minimal extent
C. It causes less hangover than nitrazepam
D. It causes rebound insomnia
E. It increases REM sleep
Answer» F.
123.

Regarding antiseptic agents all of the following are true EXCEPT

A. Sodium hypochlorite is an effective antiseptic for intact skin
B. Potassium permanganase is an effective bactericidal agent
C. Formaldehyde may be used to disinfect instruments
D. Chlorhexidine is active against gram positive cocci
E. Ethanol is an effective skin antiseptic because it denatures microbial proteins
Answer» B. Potassium permanganase is an effective bactericidal agent
124.

Regarding GABA: all the following are true EXCEPT

A. Receptor blockers have anticonvulsant activity
B. Is found in high concentrations in the basal ganglia
C. Concentrations in the basal ganglia are abnormally low in Huntington s chorea
D. Metabolism is inhibited by sodium valproate
E. Receptors are sensitive to the activity of benzodiazepines
Answer» B. Is found in high concentrations in the basal ganglia
125.

All of the following are true regarding penicillins EXCEPT

A. Most penicillins only cross the blood brain barrier when the meninges are inflamed.
B. Penicillins don t require dosage adjustment in renal failure
C. Penicillins inhibit cross linkage of peptidoglycans in the cell wall
D. Piperacillin is a penicillin active against pseudomonas
E. Only about 5 to 10% of people with a past history of penicillin allergy have a reaction on re exposure
Answer» C. Penicillins inhibit cross linkage of peptidoglycans in the cell wall
126.

Regarding the azole group of antifungals

A. Fluconazole has low water solubility
B. Ketoconazole may be given IV/PO
C. Itraconazole undergoes renal elimination
D. Clotrimazole is the treatment of choice for systemic candidiasis given orally
E. They work by reduction of ergosterol synthesis by inhibition of fungal cytochrome P450 enzymes
Answer» F.
127.

Regarding antipsychotics as a group

A. Metabolites are important to the action of these drugs
B. Haloperidol has a higher systemic availability than thioridazine or chlorpromazine
C. Elimination half lives of these drugs range between 3 6 hours
D. This group of drugs generally has short clinical duration of action
E. Clozipine is a member of the dihydroindolone group
Answer» C. Elimination half lives of these drugs range between 3 6 hours
128.

Lithium

A. Has rapid onset of action
B. Is partially renally excreted
C. Has no neurological side effects
D. Has no contraindications to be given in conjunction with NSAIDS
E. Is contraindicated in sick sinus syndrome
Answer» F.
129.

Which of the following antipsychotics (in excess dose) is responsible for cardiac arrhythmias?

A. Chlorpromazine
B. Clozapine
C. Thioridazine
D. Haloperidol
E. Thiothixene
Answer» D. Haloperidol
130.

Regarding mechanisms of antiviral drug action

A. blockage of viral uncoating is caused by rifampicin
B. Zidovudine is a protease inhibitor
C. Amantidine blocks viral DNA packaging and assembly
D. Indinavir is a reverse transcriptase inhibitor
E. Acyclovir inhibits viral DNA synthesis
Answer» F.
131.

Plasma lithium levels (assuming no change in daily lithium dose) may become toxic in the presence of all of the following EXCEPT

A. Pregnancy
B. Use of thiazides
C. Dehydration
D. Use of some non-steroidal anti-inflammatory drugs
E. Post partum state
Answer» B. Use of thiazides
132.

Which of the following drugs cause diuresis by the mechanisms indicated?

A. Ethanol by preventing the reabsorption of sodium from renal tubular fluid
B. Digoxin by inhibiting release of ADH
C. Dopamine by inhibiting active transport of chloride over the entire length of the descending limb of the loop of Henle
D. Frusemide by inhibiting carbonic anhydrase
E. Chlorothiazide by inhibiting active sodium transport in the ascending limb of the loop of Henle
Answer» F.
133.

Which of the following drugs is 99% protein bound in plasma

A. Gentamicin
B. Theophylline
C. Carbamazepine
D. Atenolol
E. Diazepam
Answer» F.
134.

Which of the following drugs is contraindicated (absolutely) in a patient with porphyria

A. Zolpidem
B. Chloral hydrate
C. Buspirone
D. Phenobarbitone
E. Diazepam
Answer» E. Diazepam
135.

Which of the following side effects for given drugs is wrong

A. Phenytoin gum hypertrophy
B. Ethosuximide hirsuitism
C. Phenobarbital enzyme induction
D. Carbamazepine ataxia
E. Valproate idiosyncratic hepatic toxicity
Answer» C. Phenobarbital enzyme induction
136.

Which of the following drugs is potentially dangerous in a single drug overdose

A. Moclobemide
B. Paroxetine
C. Sertraline
D. Trazodone
E. Amoxapine
Answer» F.
137.

Which drug regimen is suggested for severe community acquired pneumonia initially?

A. benzyl penicillin and gentamicin and erythromycin
B. benzyl penicillin and gentamicin
C. ceftriaxone and gentamicin
D. gentamicin and erythromycin
E. flucloxacillin and gentamicin
Answer» B. benzyl penicillin and gentamicin