Explore topic-wise MCQs in Biology.

This section includes 62 Mcqs, each offering curated multiple-choice questions to sharpen your Biology knowledge and support exam preparation. Choose a topic below to get started.

1.

Which is incorrect regarding encephalitis?

A. MRI shows characteristic temporal and frontal lobe changes in HSV.
B. CSF usually shows aseptic meningitis.
C. PCR for HSV is insensitive but very specific.
D. Acyclovir has only been shown to be effective in HSV, but is also used in herpes zoster encephalitis.
E. Mortality from HSV is higher than herpes zoster or CMV.
Answer» D. Acyclovir has only been shown to be effective in HSV, but is also used in herpes zoster encephalitis.
Discussion
2.

Which is INCORRECT regarding cerebral abscess?

A. Classical triad of headache, fever and focal neurological deficit occurs in over 80% of patients.
B. CT without contrast may miss the diagnosis.
C. Lumbar puncture is contraindicated.
D. Spread is haematogenous, contiguous or from neursurg or penetrating trauma.
E. Anaerobes predominate as infecting organisms.
Answer» B. CT without contrast may miss the diagnosis.
Discussion
3.

Which is NOT correct regarding migraines?

A. Prevalence is higher in woman.
B. Most improve during pregnancy
C. It is idiopathic, and usually last less than 72 hrs.
D. Ketorolac has been shown to be superior to chlorpromazine in the management of migraines.
E. Sumatriptan is contraindicated in pregnancy.
Answer» E. Sumatriptan is contraindicated in pregnancy.
Discussion
4.

Which is NOT true of non-traumatic subarachnoid haemorrhage?

A. Most common in the 40-60 year age group.
B. 70% are due to AV malformations.
C. Female: male = 2:1
D. Smoking increases your risk 3-10 fold.
E. 50% of patients die or are permanently disabled from the initial event.
Answer» C. Female: male = 2:1
Discussion
5.

Which is INCORRECT regarding investigation of SAH?

A. Non contrast CT becomes less sensitive with time following bleed.
B. 5-10% of patients with negative CT will have SAH.
C. Presence of xanthochromia is the gold standard for diagnosing SAH on LP.
D. Xanthochromia is present in all patients with SAH at 6 hrs post bleed.
E. MRI angiography is not reliable enough to use for diagnosis and surgical planning of patients with proven SAH.
Answer» E. MRI angiography is not reliable enough to use for diagnosis and surgical planning of patients with proven SAH.
Discussion
6.

Which is INCORRECT regarding treatment and complications of SAH?

A. Nimodipine has only been proven to be of benefit orally in preventing vasospasm.
B. 10-30% of patients will rebleed, with 20% within the first 2 weeks.
C. Vasospasm and delayed neurological deficit peak at day 1 post bleed.
D. Hyponatremia is common due to excessive naturesis.
E. The ECG often shows non-specific changes of widened QRS, prolonged QT and ST and T changes suggestive of ischaemia.
Answer» D. Hyponatremia is common due to excessive naturesis.
Discussion
7.

Which is true regarding the presentation of SAH?

A. Up to 20% experience a sentinel bleed.
B. A sixth cranial nerve palsy can represent a growing aneurysm in cavernous sinus.
C. Seizures occur in 50% of patients.
D. Photophobia is often more marked than patients with migraines.
E. Syncope occurs in the minority of patients.
Answer» C. Seizures occur in 50% of patients.
Discussion
8.

What is the survival rate of a Hunt and Hess Grade 5 SAH?

A. 0%
B. 5%
C. 10%
D. 15%
E. 20%
Answer» D. 15%
Discussion
9.

Which is NOT correct regarding temporal arteritis?

A. Majority older than 50 yrs.
B. More common in men.
C. Ischaemic optic neuritis is most feared complication.
D. Up to 50% of patients also have polymyalgia rheumatica.
E. Jaw claudication in the history is highly suggestive of temporal arteritis.
Answer» C. Ischaemic optic neuritis is most feared complication.
Discussion
10.

Which is INCORRECT of treatment of TIA s?

A. Aspirin 150 mg/day reduces risk of subsequent stroke by about 30%.
B. Clopidagrel was shown in the CAPRIE study to have a slight advantage over aspirin in stroke prevention.
C. Anticoagulation of patients with TIA s secondary to thrombosis has been shown to improve outcome.
D. Carotid endarterectomy will reduce death rate by almost 50% in patients with greater than 80% stenosis.
E. Patients with considerable carotid stenosis (>70%), should be admitted for anticoagulation pending consideration for surgery.
Answer» D. Carotid endarterectomy will reduce death rate by almost 50% in patients with greater than 80% stenosis.
Discussion
11.

Which is INCORRECT regarding cerebral infarction?

A. 80% are MCA territory.
B. MCA syndrome is usually embolic, and arm is usually more affected than leg.
C. Lacunar infarcts usually have partial or complete recovery over 4-6 weeks.
D. Lateral medullary syndrome can result in ipsilateral UMN 7, 9 & 10 CN palsy and Horner s syndrome with contralateral spinothalamic loss.
E. Internuclear ophthalmoplegia usually results from anterior cerebral artery occlusion.
Answer» F.
Discussion
12.

Which is true of thrombolysis in cerebral infarct?

A. Clear benefit has been shown in at least 2 randomized controlled trials that TPA reduces mortality in CVA.
B. Patients up to 6 hrs post infarct have been shown to benefit from thrombolysis.
C. Larger infarcts tend to have more benefit from thrombolysis.
D. The NINDS trial showed that improvement in patients treated within 3 hrs with thrombolysis.
E. ECASS trial thrombolysed patients within 3 hrs with TPA and showed improvements in all outcomes compared with placebo.
Answer» F.
Discussion
13.

Which is not an early sign of cerebral infarction on CT?

A. Loss of cortical grey/white matter distinction.
B. Effacement of cortical sulci
C. Compression of ventricular system
D. Hyper dense clot in MCA.
E. All are possible early signs of infarct.
Answer» F.
Discussion
14.

Which feature of vertigo is more likely to make it central rather than peripheral?

A. Fast phase of nystagmus toward lesion.
B. Horizontal or rotational nystagmus present.
C. Severe vertigo associated with vomiting and diaphoresis.
D. Visual fixation improves nystagmus.
E. Hall pike manoeuvre positive.
Answer» B. Horizontal or rotational nystagmus present.
Discussion
15.

Which statement regarding peripheral vertigo is incorrect?

A. Labyrinthitis is the most common cause.
B. BPPV is characterized by a latency period of 1-5 secs between provocative head position and onset of nystagmus.
C. Tinnitus and hearing loss are associated with Meniere s disease.
D. Vestibular neuronitis is typically non recurring.
E. Acoustic neuromas typically cause gradual onset of vertigo.
Answer» B. BPPV is characterized by a latency period of 1-5 secs between provocative head position and onset of nystagmus.
Discussion
16.

Which statement regarding central vertigo is incorrect?

A. Cerebellar CVA s will often present with truncal ataxia.
B. Vertebrobasilar insufficiency will produce vertigo lasting typically less than a few mins.
C. Multiple sclerosis can cause vertigo which typically lasts a few mins and is recurring.
D. Vertigo can be associated with migraines either as aura or part of the migraine.
E. Wallenberg syndrome or lateral medullary infarction of brainstem is associated with vertigo and Horner s syndrome
Answer» D. Vertigo can be associated with migraines either as aura or part of the migraine.
Discussion
17.

Which of the following drugs is unlikely to cause seizure in withdrawal/

A. Cocaine
B. Narcotics
C. Benzodiazepines
D. Alcohol
E. Tricyclics
Answer» F.
Discussion
18.

Which statement is incorrect regarding treatment of seizures?

A. Diazepam has the most rapid onset of the BDZ s.
B. The LD of phenytoin needs to be decreased in renal impairment.
C. Phenobarbital has duration of action of 3 days.
D. Paraldehyde can be used rectally at a dose of 0.3mls/kg.
E. Phenytoin is usually ineffective in seizures secondary to alcohol withdrawal or intoxication.
Answer» C. Phenobarbital has duration of action of 3 days.
Discussion
19.

Which is incorrect of seizures?

A. There is decreased risk of seizures in pregnancy.
B. Eclamptic seizures are typically brief, self-terminating preceded by headache and visual disturbances.
C. Pseudo seizures are often recognized by pelvic thrusting which occurs in 45%.
D. Classic ethanol withdrawal seizures occur 6-48 hrs post withdrawal but can occur up to one week after withdrawal.
E. Seizures in HIV patients are usually secondary to intracranial pathology and all require urgent CT scan.
Answer» B. Eclamptic seizures are typically brief, self-terminating preceded by headache and visual disturbances.
Discussion
20.

Which is incorrect regarding status epilepticus?

A. Mortality at 60 mins of status is around 30%.
B. Leucocytosis up to 20,000 is very common.
C. SE occurs most commonly in patients without prior hx of seizures and in extremes of age.
D. In phase 1 there is increased cerebral metabolism, hyperglycaemia, hyperpyrexia and hypertension.
E. Muscle relaxants should be used in intubated patients to avoid self- inflicted injury.
Answer» F.
Discussion
21.

Which is INCORRECT regarding the aetiology of seizures?

A. Idiopathic seizures usually start age 5-20 yrs.
B. Post head trauma seizures usually begin within 2 years of trauma.
C. Acute strokes are the most common cause in > 65 yr olds.
D. Space occupying lesions account for 1% of new seizures age 35-65.
E. Phenylketonuria may cause seizures.
Answer» E. Phenylketonuria may cause seizures.
Discussion
22.

Which of the following peripheral neurological nerve lesions will not result in proximal weakness greater than peripheral?

A. Radiculopathy
B. Neuropathy
C. Neuromuscular junction disease
D. Myopathy
E. All of the above result in more marked proximal weakness.
Answer» C. Neuromuscular junction disease
Discussion
23.

Which is INCORRECT regarding myasthenia gravis?

A. Onset in females usually 2nd and 3rd decades, males 7th and 8th decades.
B. The thymus is abnormal in 75% and removal will improve symptoms in the majority.
C. Acute crises in these patients can be due to myasthenia crisis or cholinergic crisis secondary to the medication.
D. Muscle weakness is more marked peripherally.
E. Diagnosis with Ach receptor antibody testing is possible but false negatives occur in 15%.
Answer» E. Diagnosis with Ach receptor antibody testing is possible but false negatives occur in 15%.
Discussion
24.

Which is incorrect regarding Guillain Barre Syndrome?

A. 80% of patients will have antecedent infection with Campylobacter jejuni.
B. CSF will show low protein, high glucose and often a pleocytosis up to 100.
C. High dose immune globulin and plasmapheresis have been shown to be equally efficacious in reducing length of illness.
D. Severe cases will not only involve demyelination but also axonal degeneration.
E. 85% will recover to their previous normal functioning in one year.
Answer» B. CSF will show low protein, high glucose and often a pleocytosis up to 100.
Discussion
25.

Which is INCORRECT regarding entrapment neuropathies?

A. Carpal tunnel syndrome usually produces more pain at night.
B. Bell s palsy cause sudden facial weakness with peak paralysis seen at 48 hrs.
C. Use of steroids and acyclovir has been advocated for treatment of Bell s palsy as one study showed reduced length of paralysis.
D. Entrapment of deep peroneal nerve will result in foot drop and paraesthesia between big toe and second toe.
E. Ulnar nerve entrapment usually occurs at the wrist resulting in numbness of 5th digit and half of 4th digit.
Answer» F.
Discussion
26.

Which statement is INCORRECT regarding multiple sclerosis?

A. It is 2-3 times more common in females
B. The most common reported symptom initially is sensory loss.
C. Optic neuritis is usually unilateral can afferent pupillary response may be present.
D. The majority of patients will show plaques on MRI T2 weighted scans.
E. CSF often shows elevated protein, gamma-globulin and slightly elevated WCC.
Answer» C. Optic neuritis is usually unilateral can afferent pupillary response may be present.
Discussion
27.

How long should you wait to get an LP before giving antibiotics?

A. give antibiotics immediately
B. 10 mins
C. 20 mins
D. 30 mins
E. 45 mins
Answer» D. 30 mins
Discussion
28.

Which of the signs or symptoms below would concern you that the cause of a patients vertigo was central?

A. associated vomiting
B. worsens with position change
C. associated tinnitus
D. vertical nystagmus
E. sudden onset
Answer» E. sudden onset
Discussion
29.

Which statement is incorrect about prophylaxis in meningitis?

A. there is no prophylaxis available for pneumococcus only meningococcus and Hib
B. it does not need to be given to the index case
C. it should include all household contact where there has been close contact eg. Share eating utensils
D. it should be given to the attending medical staff only if they did mouth to mouth
E. rifampicin or ceftriaxone or ciprofloxacin are in the drugs involved
Answer» C. it should include all household contact where there has been close contact eg. Share eating utensils
Discussion
30.

Which of these is not consistent with vestibular neuronitis?

A. horizontal nystagmus
B. dysarthria
C. vomiting
D. constant for eight hours
E. vertigo
Answer» C. vomiting
Discussion
31.

A patient with a SAH has a severe headache with nuchal rigidity but no focal neurological signs.What is her Hunt and Hess classification?

A. 1
B. 2
C. 3
D. 4
E. 5
Answer» C. 3
Discussion
32.

A patient presents with right sided arm weakeness and a R facial droop with aphasia. Which artery distribution is the likely to be the cause of her stoke?

A. right MCA
B. left MCA
C. right anterior cerebral artery
D. left anterior cerebral artery
E. left vertebrobasilar system
Answer» C. right anterior cerebral artery
Discussion
33.

Which is true of the recent trial (NINDS) of thrombolysis in acute ischemic stroke?

A. streptokinase has the same risk benefit profile as tPA
B. the mortaility rate of tPA given within three hours of onset of ischemic stroke is lower than that of the stoke without thrombolysis
C. the mortality rate of tPA given within three hours of onset of ischemic stroke is higher than that of the stoke without thrombolysis
D. the long term disability rate in patients surviving their stoke is less if they were given tPA
E. the long term disability rate in patients surviving their stoke is higher if they were given tPA
Answer» E. the long term disability rate in patients surviving their stoke is higher if they were given tPA
Discussion
34.

Which statement is FALSE about carotid stenoses?

A. in a patient with an anterior circulation ischemic event, the presence of a bruit suggests a moderately severe stenosis
B. in a patient with an anterior circulation ischemic event, the absence of a bruit dismisses a moderately severe stenosis
C. a symptomatic stenosis >70% is often operated upon
D. an asymptomatic stenosis of > 70% is usually not operated upon
E. all patient with stenoses < 30% should not be considered for endarterectomy
Answer» C. a symptomatic stenosis >70% is often operated upon
Discussion
35.

What percentage of the population will have at least one seizure in their lifetime?

A. 2.5%
B. 5%
C. 10%
D. 15%
E. 17.5%
Answer» D. 15%
Discussion
36.

When would heparin be given in an ischemic stroke or TIA?

A. all
B. vertebro basilar ischemic stroke
C. anterior circulation ischemic stroke with no prior history of cerebrovascular disease
D. ischemic stroke or TIA secondary to proven cardioembolic source
E. lacunar infarct with 80% carotid stenosis
Answer» E. lacunar infarct with 80% carotid stenosis
Discussion
37.

Which statement is incorrect with regards to non contrast CT in SAH

A. <12 hours =97.5% detection
B. 24 hours=95% detection
C. 1 week 50% detection
D. 3 days = 75% detection
E. 1 hour= 100% detection
Answer» F.
Discussion
38.

Which statement is INCORRECT with regards to vasospasm in SAH?

A. it usually occurs at day 4-14
B. it effects 30% of pts with SAH
C. it has a 30% morbidity and mortality untreated
D. hypertensive therapy with iv fluids and inotropes is contrindicated
E. the treatment of choice is Nimodipine
Answer» E. the treatment of choice is Nimodipine
Discussion
39.

What percentage of pts with SAH have a prior sentinal warning hemorrhage ?

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

How long does a pt have to be seizing for to be in Status Epilepticus?

A. 20 mins
B. 30 mins
C. 40 mins
D. 50 mins
E. 60 mins
Answer» C. 40 mins
Discussion
41.

Which statement is false about benzodiazepines and seizures?

A. there is little evidence to support any particular one
B. the dose of clonazepam in a child is 0.5 mg, and an adult 1mg
C. diazepam can be safely used PR, IM or IV
D. the rectal dose of diazepam for a 3 year old is about 5mg
E. the IV dose of diazepam in a 1 year old is about 2-3mg
Answer» D. the rectal dose of diazepam for a 3 year old is about 5mg
Discussion
42.

Which statement is FALSE regarding other headaches?

A. cluster headaches are short lived lasting 15-180 mins
B. oxygen can releve a majority of cluster headaches
C. temperal arteritis usually produces an ESR of 20
D. temporal arteritis can cause ischemic optic neuritis if left untreated
E. treatment of temperal arteritis involves oral prednisolone
Answer» D. temporal arteritis can cause ischemic optic neuritis if left untreated
Discussion
43.

Which statement is false about Phenytoin?

A. the loading dose is 15-20 mg/kg
B. if a pt on phenytoin arrives in status epilepticus then the full loading dose should still be given
C. side effects include hypotension and bradyarrythmias
D. it is extremely effective in alcohol induced seizures
E. it is contraindicated in 2nd and 3rd degree heart block
Answer» E. it is contraindicated in 2nd and 3rd degree heart block
Discussion
44.

Which interventions are NOT recommended and proven in Australia for treatment of ischemic strokes?

A. thrombolysis if less than 3 hours and normal CT
B. aspirin
C. specialized stoke unit
D. warfarin if atrial fibrillation
E. clopridogil
Answer» B. aspirin
Discussion
45.

Which is not a risk factor for subarachnoid haemorrhage?

A. female
B. 1st degree relative with SAH
C. polycystic ovaries
D. smoking
E. Marfans syndrome, coarctation of the aorta
Answer» D. smoking
Discussion
46.

Which statement is incorrect regarding meningitis?

A. 90% of cases occur in the first 5 years, with peak at 6 months of age.
B. Damage is due to the inflammatory response not bacterial toxins.
C. Brudzinski s sign is involuntary hip flexion with passive neck flexion.
D. CT may be normal even in the presence of elevated ICP in up to 45%.
E. LP is always abnormal with bacterial meningitis.
Answer» F.
Discussion
47.

Which statement is FALSE about zanthocromia and SAH?

A. Inspection of CSF with the naked eye reliably detects zanhtochromia
B. it is present in all CSF at 6 hours
C. it remains in CSF for 2 weeks
D. it is not present in a traumatic tap
E. it is detected with spectrophotometry
Answer» C. it remains in CSF for 2 weeks
Discussion
48.

Which of the features below is not consistent with a pseudoseizure?

A. rhythmic thrusting of the pelvis
B. extremity movements out of phase bilaterally
C. head rolling from side to side
D. recall of events during the seizure
E. tongue biting
Answer» F.
Discussion
49.

What is the recommended antibiotic regimen for empirical treatment of bacterial meningitis in a 40 year old?

A. Ceftriaxone 2gm and Benzylpenicillin 1.8gm
B. Ceftriaxone 2gm
C. Benzylpenicillin 1.8gm
D. Ceftriaxone 2gm and Benzylpenicillin 1.8gm and Vancomycin 500mg
E. Ceftriaxone 2gm and Vancomycin 500mg
Answer» B. Ceftriaxone 2gm
Discussion
50.

Which statement is FALSE regarding migraine?

A. pathophysiology involves inflammation of the trigeminovascular system
B. serotonin plays an integral part
C. the aura, if present, should last less than 60 mins and be totally reversible
D. it is typically bilateral, pulsating and occipital
E. the headache usually last 4-72 hours
Answer» E. the headache usually last 4-72 hours
Discussion