Anatomy
2 questionsA patient presented to OPD with ophthalmoplegia and ptosis. Diagnosis of superior orbital fissure syndrome was confirmed after examination. Which nerves are compressed in this case ?
The artery that is palpated between the medial malleolus and the calcaneal tendon is?
FMGE 2025 - Anatomy FMGE Practice Questions and MCQs
Question 461: A patient presented to OPD with ophthalmoplegia and ptosis. Diagnosis of superior orbital fissure syndrome was confirmed after examination. Which nerves are compressed in this case ?
- A. III, IV, V1, V2
- B. III, IV, V1, VI (Correct Answer)
- C. II, III, IV, V1
- D. II, III, IV, VI
Explanation: ***III, IV, V1, VI*** - The **superior orbital fissure** is a critical anatomical passage that transmits the **oculomotor nerve (III)**, **trochlear nerve (IV)**, the **ophthalmic division of the trigeminal nerve (V1)**, and the **abducens nerve (VI)**. - Compression of these nerves collectively results in **ophthalmoplegia** (paralysis of eye muscles due to III, IV, VI involvement [1]) and **ptois** (drooping of the upper eyelid due to III involvement), which are the classic signs of superior orbital fissure syndrome. *III, IV, V1, V2* - This option is incorrect because the **maxillary division of the trigeminal nerve (V2)** does not pass through the superior orbital fissure. - V2 exits the skull through the **foramen rotundum** to supply the maxillary region, and is therefore not affected in this syndrome. *II, III, IV, VI* - This option is incorrect because the **optic nerve (II)** is not involved in superior orbital fissure syndrome. - The optic nerve passes through the **optic canal**, a separate opening. Involvement of the optic nerve would cause vision loss and indicate a more extensive condition like **orbital apex syndrome**. *II, III, IV, V1* - This is incorrect as it includes the **optic nerve (II)**, which, as mentioned, travels through the optic canal, not the superior orbital fissure. - The absence of vision loss or an **afferent pupillary defect** helps differentiate superior orbital fissure syndrome from pathologies involving the optic nerve.
Question 462: The artery that is palpated between the medial malleolus and the calcaneal tendon is?
- A. Popliteal artery
- B. Anterior tibial artery
- C. Dorsalis pedis artery
- D. Posterior tibial artery (Correct Answer)
Explanation: ***Posterior tibial artery*** - This artery passes through the **tarsal tunnel**, located just posterior to the **medial malleolus** and anterior to the **calcaneal (Achilles) tendon**, making it the palpable artery at this specific site. - The **posterior tibial artery** pulse is a critical component of the lower limb vascular examination, essential for assessing blood supply to the foot, especially in cases of **peripheral arterial disease** [1]. *Anterior tibial artery* - This artery is located on the **anterior aspect** of the leg and ankle, running down the front of the leg between the tibia and fibula. - It becomes the **dorsalis pedis artery** as it crosses the ankle joint, so it is not found behind the medial malleolus. *Dorsalis pedis artery* - This artery is palpated on the **dorsum (top) of the foot**, typically lateral to the tendon of the extensor hallucis longus. - As a continuation of the **anterior tibial artery**, its pulse point is anatomically distinct from the area between the medial malleolus and the calcaneal tendon. *Popliteal artery* - The **popliteal artery** is found deep within the **popliteal fossa**, the space behind the knee joint. - It is a much more proximal vessel that bifurcates into the **anterior and posterior tibial arteries** well above the ankle.
Biochemistry
1 questionsA patient presents with multiple colonic polyps and has been diagnosed with colorectal carcinoma. There is a strong family history of Hereditary Non-Polyposis Colorectal Cancer (HNPCC). Which DNA repair mechanism is most likely defective in this condition?
FMGE 2025 - Biochemistry FMGE Practice Questions and MCQs
Question 461: A patient presents with multiple colonic polyps and has been diagnosed with colorectal carcinoma. There is a strong family history of Hereditary Non-Polyposis Colorectal Cancer (HNPCC). Which DNA repair mechanism is most likely defective in this condition?
- A. Double-strand break repair
- B. Nucleotide excision repair
- C. Base excision repair
- D. Mismatch repair (Correct Answer)
Explanation: ***Mismatch repair***- **HNPCC (Lynch syndrome)** is caused by inherited germline mutations in genes (e.g., *MLH1*, *MSH2*) that are responsible for the **mismatch repair (MMR)** pathway. - The failure of MMR leads to the accumulation of errors, specifically in repetitive DNA sequences, resulting in **microsatellite instability** which drives carcinogenesis.*Nucleotide excision repair*- This mechanism repairs bulky helix-distorting lesions in DNA, most commonly **pyrimidine dimers** caused by UV radiation. - A classic disease associated with defective **NER** is **Xeroderma Pigmentosum**, which presents with extreme sun sensitivity and a high risk of skin cancers.*Base excision repair*- This pathway primarily corrects small, non-helix distorting damage, such as oxidized or alkylated bases, utilizing enzymes like **DNA glycosylases**.- While fundamental for DNA maintenance, primary defects in BER are not the underlying cause of pathogenesis in **Lynch syndrome**.*Double-strand break repair*- This mechanism repairs severe damage where the entire DNA helix is broken, typically via **Homologous Recombination (HR)** or **Non-Homologous End Joining (NHEJ)**. - Defects in HR are often linked to hereditary breast and ovarian cancers (e.g., *BRCA1*/ *BRCA2* mutations) and are distinct from the pathogenesis of **HNPCC**.
Forensic Medicine
1 questionsA deceased woman was sent for an autopsy. She was found dead in a locked room with a heat stove still running. What is the most likely cause of death?
FMGE 2025 - Forensic Medicine FMGE Practice Questions and MCQs
Question 461: A deceased woman was sent for an autopsy. She was found dead in a locked room with a heat stove still running. What is the most likely cause of death?
- A. Cyanide poisoning
- B. H₂S poisoning
- C. Aluminium phosphide poisoning
- D. CO poisoning (Correct Answer)
Explanation: ***CO poisoning***- The context of a deceased person in a locked room with a running heat stove points strongly to inhalation of **Carbon Monoxide (CO)**, a colorless, odorless gas produced by incomplete combustion.- CO has a very high affinity for **hemoglobin**, forming **carboxyhemoglobin**, which impairs oxygen transport and causes death via chemical **asphyxia**.*Cyanide poisoning*- Cyanide prevents cellular oxygen utilization (histotoxic hypoxia) by non-competitively inhibiting **cytochrome oxidase** in the mitochondria.- While highly fatal, cyanide is usually associated with the smell of **bitter almonds** at the scene and is not typically produced by household heat stoves.*H₂S poisoning*- **Hydrogen sulfide (H₂S)** poisoning is characterized by a distinctive odor of **rotten eggs** and is frequently associated with occupational exposure (e.g., sewers or drilling).- This gas also causes tissue hypoxia by inhibiting cellular respiration, but the circumstances described favor simple CO production from combustion.*Aluminium phosphide poisoning*- **Aluminium phosphide (ALP)** liberates **phosphine gas** upon exposure to moisture or stomach acid, leading to systemic toxicity.- This type of poisoning is usually due to deliberate ingestion of pesticides and causes severe effects, particularly on the **myocardium**, which is inconsistent with the presented scenario.
Physiology
4 questionsWhich of the following ion movements is primarily responsible for the repolarization phase (Phase 3) of an action potential, as depicted in the image?
Which among the following hormones, in a lactating mother, is responsible for the maintenance and proliferation of milk-secreting breast tissue?
A 35-year-old man wakes up after sleeping with his arm draped over a chair and complains of pain. Which of the following accurately describes the order of susceptibility of nerve fibers in the given condition?
A woman from Delhi travels to Ladakh, a high-altitude region. Soon after arrival, she develops symptoms such as breathlessness, headache, and lightheadedness. What is the primary underlying mechanism responsible for her symptoms?
FMGE 2025 - Physiology FMGE Practice Questions and MCQs
Question 461: Which of the following ion movements is primarily responsible for the repolarization phase (Phase 3) of an action potential, as depicted in the image?
- A. Efflux of K ions (Correct Answer)
- B. Influx of Na ions
- C. Efflux of Na ions
- D. Resting membrane potential is maintained by the Na-K pump
Explanation: ***Efflux of K ions*** - Phase 3, the **repolarization** or falling phase, is initiated by the opening of voltage-gated **potassium (K+) channels** as the membrane potential peaks. - The outflow of positive K+ ions from the cell, known as **efflux**, causes the membrane potential to become negative again, returning it towards the resting state. *Efflux of Na ions* - The electrochemical gradient for **sodium (Na+)** strongly favors its movement into the cell (influx), not out of it (efflux). - While the **Na+/K+ pump** does move Na+ out of the cell, this is a slow, active process to maintain resting potential, not the cause of rapid repolarization. *Influx of Na ions* - The rapid influx (inflow) of **Na+** ions through voltage-gated channels is responsible for the **depolarization** phase (Phase 0), the sharp upstroke of the action potential. - During repolarization (Phase 3), these voltage-gated **Na+ channels** become inactivated, stopping the influx. *Resting membrane potential is maintained by the Na-K pump* - The **Na+/K+ pump** is crucial for establishing and maintaining the ion gradients for the **resting membrane potential** (Phase 4), not for the rapid repolarization phase itself. - Repolarization is a passive process resulting from ion flow through channels, which is much faster than the action of the Na+/K+ pump.
Question 462: Which among the following hormones, in a lactating mother, is responsible for the maintenance and proliferation of milk-secreting breast tissue?
- A. Estrogen
- B. Oxytocin
- C. Prolactin (Correct Answer)
- D. Progesterone
Explanation: ***Prolactin***- **Prolactin** is the key hormone responsible for establishing and maintaining **lactation** (milk production), and it drives the final proliferation and differentiation of the **alveolar epithelial cells** during the later stages of pregnancy and postpartum state.- While other hormones contribute to overall breast development, Prolactin ensures the functional readiness and continued growth/maintenance of the glandular tissue necessary for milk synthesis.*Oxytocin*- **Oxytocin** is responsible for the **milk ejection reflex** (let-down), causing the contraction of **myoepithelial cells** around the alveoli.- It does not promote the proliferative growth or differentiation of the secretory breast tissue itself.*Estrogen*- **Estrogen** is primarily responsible for the growth and development of the **ductal system** of the breast during puberty and pregnancy.- High levels of estrogen during pregnancy actively **inhibit** the full secretory function of prolactin until after delivery.*Progesterone*- **Progesterone** is crucial for the development of the **lobular-alveolar system** during pregnancy.- Its rapid decline after delivery is essential to remove the inhibitory block, allowing **prolactin** to fully initiate and manage milk secretion in the lactating phase.
Question 463: A 35-year-old man wakes up after sleeping with his arm draped over a chair and complains of pain. Which of the following accurately describes the order of susceptibility of nerve fibers in the given condition?
- A. C < B < A
- B. A < B < C
- C. C > B > A
- D. A > B > C (Correct Answer)
Explanation: ***A > B > C***- The clinical scenario describes **neuropraxia** (transient functional block) due to **compression and ischemia**, such as in 'Saturday night palsy'.- A fibers have the largest diameter and the heaviest myelination, making them the most vulnerable to conduction block resulting from **focal demyelination** caused by mechanical stress. *A < B < C*- This sequence incorrectly places the greatest susceptibility on the smallest, unmyelinated **C fibers**.- C fibers transmit **slow pain** and temperature and are known to be the most resilient nerve type to compression and ischemia. *C > B > A*- This order represents the susceptibility of nerve fibers to **local anesthetic agents** (pharmacologic block), not mechanical compression. - Local anesthetics preferentially block smaller, unmyelinated C fibers (pain and temperature sensation), followed by B and then A fibers (motor/proprioception). *C < B < A*- While mathematically consistent with **A being the most susceptible**, this alternative formatting is less commonly used to denote the decreasing order of susceptibility (A fibers > B fibers > C fibers) to compression injury.
Question 464: A woman from Delhi travels to Ladakh, a high-altitude region. Soon after arrival, she develops symptoms such as breathlessness, headache, and lightheadedness. What is the primary underlying mechanism responsible for her symptoms?
- A. Metabolic alkalosis
- B. Metabolic acidosis
- C. Respiratory acidosis
- D. Respiratory alkalosis (Correct Answer)
Explanation: ***Respiratory alkalosis***- Acute exposure to high altitude decreases the **partial pressure of inspired oxygen ($P_{I}O_2$)**, leading to **hypoxemia**, which stimulates the peripheral chemoreceptors (carotid bodies) to increase the respiratory drive (hyperventilation).- This hyperventilation causes a massive *washout* of **carbon dioxide ($ ext{CO}_2$)**, resulting in low arterial $ ext{P}_{ ext{a}} ext{CO}_2$ (hypocapnia) and an immediate increase in blood $ ext{pH}$ (alkalosis).*Respiratory acidosis*- This condition is characterized by **hypoventilation** resulting in the retention of $ ext{CO}_2$ and a resultant drop in $ ext{pH}$.- Acute high altitude exposure leads to increased ventilation (hyperventilation), making this mechanism incorrect.*Metabolic alkalosis*- This state results from excess plasma **bicarbonate ($ ext{HCO}_3^{-})$** or significant loss of $ ext{H}^{+}$ (e.g., protracted vomiting, loop diuretics).- This is not the primary acid-base disturbance leading to acute mountain sickness (AMS) symptoms.*Metabolic acidosis*- This state is the **delayed renal compensatory mechanism** for respiratory alkalosis, where the kidneys increase the excretion of $ ext{bicarbonate}$.- While it occurs, it is a secondary compensation that takes 24–48 hours and is not the *primary underlying mechanism* responsible for the immediate symptoms upon arrival.
Psychiatry
1 questionsAn alcoholic patient is admitted to the hospital 48 hours after his last drink. He presents with altered consciousness, disorientation, and severe agitation. What is the most likely diagnosis?
FMGE 2025 - Psychiatry FMGE Practice Questions and MCQs
Question 461: An alcoholic patient is admitted to the hospital 48 hours after his last drink. He presents with altered consciousness, disorientation, and severe agitation. What is the most likely diagnosis?
- A. Delirium tremens (Correct Answer)
- B. Korsakoff psychosis
- C. Alcohol withdrawal symptoms
- D. Cocaine intoxication
Explanation: ***Correct: Delirium tremens*** - **Classic presentation** with altered consciousness, disorientation, and severe agitation occurring **48 hours after last drink** (typical onset 48-72 hours) - Represents the **most severe form of alcohol withdrawal syndrome** - Clinical features include autonomic hyperactivity, confusion, visual/tactile hallucinations, and psychomotor agitation - **Medical emergency** requiring immediate treatment with benzodiazepines and supportive care - Mortality rate 5-15% if untreated *Incorrect: Korsakoff psychosis* - **Chronic condition** resulting from thiamine (vitamin B1) deficiency in chronic alcoholism - Characterized by **anterograde amnesia** and **confabulation**, not acute delirium - Does not present with acute altered consciousness or severe agitation - Timeline does not fit acute withdrawal scenario *Incorrect: Alcohol withdrawal symptoms* - While DT is technically a form of alcohol withdrawal, this option refers to **minor/uncomplicated withdrawal** - Minor withdrawal symptoms (tremors, anxiety, sweating, nausea) typically occur **6-24 hours** after last drink, not at 48 hours - The **severity** (altered consciousness, disorientation) indicates progression to DT, not simple withdrawal - Uncomplicated withdrawal does not present with delirium or significant confusion *Incorrect: Cocaine intoxication* - Patient is described as **alcoholic with 48 hours since last drink** - no history of cocaine use mentioned - Cocaine intoxication would present with **euphoria, hyperactivity, paranoia**, and cardiovascular symptoms (tachycardia, hypertension) - Timeline doesn't fit - intoxication occurs during use, not days after last alcohol consumption
Surgery
1 questionsAfter the parotidectomy operation, a patient presents with excessive sweating and redness over the parotid region. What is the diagnosis?
FMGE 2025 - Surgery FMGE Practice Questions and MCQs
Question 461: After the parotidectomy operation, a patient presents with excessive sweating and redness over the parotid region. What is the diagnosis?
- A. Bell’s Palsy
- B. Glossopharyngeal neuralgia
- C. Horner’s syndrome
- D. Frey’s Syndrome (Correct Answer)
Explanation: ***Frey’s Syndrome***- It is a common post-parotidectomy complication resulting from **aberrant regeneration** of the severed **auriculotemporal nerve**.- The parasympathetic secretomotor fibers meant for the parotid gland mistakenly reinnervate the overlying cutaneous sweat glands and blood vessels, causing **gustatory sweating** and **flushing (redness)** in the parotid region upon chewing or eating.*Horner’s syndrome*- This syndrome results from interruption of the **cervical sympathetic trunk** and presents with the classic triad of **ptosis** (droopy eyelid), **miosis** (constricted pupil), and **anhidrosis** (lack of sweating) on the affected side of the face.- It is unrelated to the auriculotemporal nerve damage common after parotidectomy and involves *lack* of sweating, contrary to the patient's complaint of *excessive* sweating.*Bell’s Palsy*- This is an **idiopathic acute peripheral facial nerve palsy**, leading to unilateral weakness or paralysis of the muscles of facial expression (e.g., inability to close the eye or raise the eyebrow).- While the facial nerve (CN VII) is at risk during parotidectomy, Bell's Palsy itself does not account for the specific symptoms of post-operative gustatory sweating and redness.*Glossopharyngeal neuralgia*- This condition involves brief, severe episodes of stabbing pain in the throat, tonsillar area, back of the tongue, or ear due to irritation of the **glossopharyngeal nerve (CN IX)**.- It is a disorder characterized purely by pain, often triggered by **swallowing** or **talking**, and is not associated with post-operative salivary gland complication symptoms like gustatory sweating.