NEET-PG 2012 Practice Questions

Q: The tensor veli palatini muscle is innervated by which nerve?

Mandibular nerve. ***Mandibular nerve*** - The **tensor veli palatini** muscle plays a crucial role in tensing the **soft palate** and opening the **Eustachian tube**. - Its innervation is by a branch of the **mandibular division of the trigeminal nerve (V3)**, specifically the nerve to the medial pterygoid. *Facial nerve* - The **facial nerve (cranial nerve VII)** primarily innervates the muscles of **facial expression**, not the muscles of the soft palate. - It also supplies the **lacrimal, submandibular, and sublingual glands** and carries **taste sensation** from the anterior two-thirds of the tongue. *Vagus nerve* - The **vagus nerve (cranial nerve X)** innervates most muscles of the **pharynx and larynx**, and some muscles of the soft palate such as the **levator veli palatini**, **palatopharyngeus**, and **palatoglossus**. - It does not, however, innervate the **tensor veli palatini**. *Glossopharyngeal nerve* - The **glossopharyngeal nerve (cranial nerve IX)** innervates the **stylopharyngeus muscle** and provides sensation to the posterior one-third of the tongue. - While it has functions related to the pharynx, it does not directly innervate the **tensor veli palatini**.

Q: Which of the following is true about cadaveric spasm?

Some particular group of muscles are involved. ***Some particular group of muscles are involved*** - **Cadaveric spasm** is characteristically a **localized or partial phenomenon**, typically affecting specific muscle groups that were in intense contraction at the moment of death. - Classic examples include **hand gripping a weapon** (homicide/suicide), **clutching grass or mud** (drowning), or **specific limb muscles** during extreme physical exertion. - While generalized cadaveric spasm can theoretically occur, it is **usually partial and localized** to the muscles involved in the terminal activity. - This is a key distinguishing feature used in **medico-legal investigations** to determine circumstances of death. *Occurs 2-3 h after death* - This describes the typical onset of **rigor mortis**, which begins 2-3 hours post-mortem and follows a predictable progression. - **Cadaveric spasm** occurs **instantaneously at the moment of death** with **no flaccid interval**, unlike rigor mortis which has a pre-rigor flaccid phase. *Disappears with rigor mortis* - This is **incorrect**. Cadaveric spasm does **not disappear** when rigor mortis develops. - Instead, cadaveric spasm **persists and merges into rigor mortis**, becoming indistinguishable from it once rigor mortis is fully established. - Both cadaveric spasm and rigor mortis eventually resolve together during the **resolution phase** (24-36 hours post-mortem), not separately. *Involves involuntary muscles* - **Cadaveric spasm** affects only **voluntary (skeletal) muscles** under conscious control. - Involuntary muscles such as cardiac muscle and smooth muscles of internal organs are **not involved** in cadaveric spasm.

Q: Marshall's triad is seen in:

Explosive injury. ***Explosive injury*** - Marshall's triad components, including **blast lung**, **abdominal hemorrhage**, and **tympanic membrane rupture**, are characteristic injuries of explosions, especially those involving pressure waves. - The triad highlights distinct patterns of organ damage caused by the high-energy transfer from blast forces. *Lightning injury* - Lightning injuries can cause diverse effects like **cardiac arrest**, **neurological damage**, and **burns**, but they do not typically present as Marshall's triad. - The primary mechanism is electrical, leading to distinct injury patterns different from blast trauma. *Gunshot injury* - Gunshot wounds create localized tissue damage along the projectile's path and a temporary cavity, but they do not cause generalized blast effects or the specific triad of Marshall. - The injury severity depends on the **caliber**, **velocity**, and **trajectory** of the bullet. *Drowning injury* - Drowning is characterized by **respiratory impairment** resulting from submersion or immersion in liquid, leading to **hypoxia** and multi-organ failure. - Its pathophysiology and presentation are entirely distinct from explosive trauma.

Q: Contributory negligence is negligence due to:

Patient only. ***Patient only*** - **Contributory negligence** specifically refers to negligence on the part of the **plaintiff** (the patient) that contributed to their own injury. - This doctrine can reduce or bar recovery for damages if the patient's own actions played a role in causing the harm. *Doctor only* - This describes **medical malpractice**, where the healthcare provider's negligence directly causes harm to the patient. - While a doctor's negligence is a primary concern in healthcare, it doesn't align with the legal concept of *contributory* negligence, which attributes fault to the injured party. *Both doctor and patient* - This scenario relates to **comparative negligence**, a legal doctrine where fault is apportioned between multiple parties (e.g., doctor and patient). - Contributory negligence, in its strict form, implies the patient's negligence alone contributed significantly enough to preclude full recovery, rather than shared fault. *Hospital administrator and doctor* - This refers to negligence stemming from actions of the hospital administration (e.g., systemic failures, inadequate resources) and individual medical errors by the doctor. - While both can be liable for negligence, this does not represent the patient's own contribution to their injury, which is the core of contributory negligence.

Q: Barium carbonate poisoning causes -

Muscular weakness. ***Correct: Muscular weakness*** - **Soluble barium salts** (barium chloride, barium nitrate, barium sulfide) are highly toxic when ingested, releasing Ba²⁺ ions - Barium blocks **potassium channels** in cell membranes, causing **intracellular shift of potassium** leading to profound **hypokalemia** - This results in **flaccid paralysis** and severe **muscular weakness**, which is the **hallmark feature** of barium poisoning - Can progress to **paralysis of respiratory muscles**, making it life-threatening - **Note:** Barium carbonate itself is **insoluble** and relatively non-toxic; toxicity occurs when converted to soluble forms in stomach acid *Incorrect: Gastrointestinal irritation* - While mild GI symptoms (nausea, vomiting, diarrhea) may occur, they are **not the dominant feature** - The primary toxicity is **neuromuscular** rather than gastrointestinal - GI irritation, when present, is overshadowed by the dramatic muscular manifestations *Incorrect: Cyanosis* - Cyanosis is not a primary feature of barium poisoning - May occur **secondarily** if respiratory muscle paralysis is severe enough to cause hypoxemia - Not a characteristic or early sign *Incorrect: Respiratory distress* - Respiratory distress occurs due to **paralysis of respiratory muscles** from hypokalemia - This is a **complication** of the muscular weakness, not the primary manifestation - While serious and potentially fatal, it represents progression of the neuromuscular toxicity

Q: In sexual assault of a child, the hymen is usually not ruptured due to:

Deep seated. ***Deep seated*** - In prepubertal children, the hymen is **deep-seated within the vaginal orifice**, positioned well inside the vaginal opening - This anatomical location provides **natural protection** from external trauma - The deep position means that superficial contact may not reach the hymenal tissue - This is the **classical forensic medicine teaching** regarding preservation of hymen in child sexual assault cases *Incorrect: Distensible* - While the child's hymen is indeed elastic and distensible (which also contributes to non-rupture), this is not the primary reason cited in forensic literature - Distensibility is a secondary protective factor *Incorrect: Too tough to rupture* - The prepubertal hymen is **not particularly tough or thick** - In fact, it is relatively thin and delicate compared to post-pubertal hymen - Toughness is not the protective mechanism *Incorrect: Underdeveloped* - The hymen is present and developed in children, just positioned differently - "Underdeveloped" does not explain the protection from rupture - The issue is **anatomical position**, not developmental status

Q: An 18-year-old girl presents with watery diarrhea. Most likely causative agent -

V. cholerae. ***V. cholerae*** - *Vibrio cholerae* is a classic cause of **acute, severe watery diarrhea** that can lead to rapid dehydration. - While other agents can cause watery diarrhea, *V. cholerae* is primarily associated with large-scale outbreaks of this symptom. *Rota virus* - While rotavirus causes **watery diarrhea**, it primarily affects **infants and young children** and is less common as the most likely cause in an 18-year-old in many settings due to widespread vaccination programs. - The diarrhea, though watery, is often accompanied by **fever and vomiting**. *Salmonella* - *Salmonella* typically causes **inflammatory diarrhea** (dysentery-like symptoms with blood/mucus in stool) or **food poisoning**, with diarrhea that may be watery but is often not as profuse or severe as cholera. - It is more commonly associated with **fever and abdominal cramps**. *Shigella* - *Shigella* causes **bacillary dysentery**, characterized by **bloody, mucoid stools**, abdominal cramps, and fever. - It is not typically associated with solely profuse watery diarrhea.

Q: Lendrum's stain is done for:

Amniotic fluid embolism. ***Amniotic fluid embolism*** - **Lendrum's stain** (MSB - Martius Scarlet Blue) is specifically used to identify **fibrin**, **mucin**, and **squamous cells** in the pulmonary vasculature, which are characteristic findings in amniotic fluid embolism. [1] - This stain excellently demonstrates **fibrin** (stains red) and helps visualize components of amniotic fluid that embolize to the mother's lungs, leading to a severe, often fatal, obstetric emergency. [1] - Lendrum's method is particularly valuable in forensic pathology and autopsy diagnosis of this condition. *Air embolism* - Air embolism diagnosis relies on identifying **air bubbles** in the cardiovascular system, often confirmed by imaging studies or direct visualization during autopsy. [1] - Special stains are not typically used for direct detection of air in tissue sections. *Pulmonary embolism* - Pulmonary embolism, typically caused by a **blood clot**, is diagnosed by identifying **fibrin** and **red blood cells** within pulmonary arteries, often with stains like hematoxylin and eosin (H&E). [1] - While Lendrum's stain can demonstrate fibrin, it is specifically employed when amniotic fluid embolism is suspected, not for routine thromboembolic disease. *Fat embolism* - **Fat embolism** is diagnosed by demonstrating **fat globules** in the pulmonary microvasculature using **fat stains** like **Oil Red O** or **Sudan Black**, usually on frozen sections. - Lendrum's stain does not specifically highlight fat emboli. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Respiratory Tract Disease, pp. 322-324.

Q: Tibolone is a ?

Synthetic steroid hormone. ***Synthetic steroid hormone*** - **Tibolone** is a **synthetic steroid** with **estrogenic, progestogenic, and weak androgenic properties** used for hormone therapy in postmenopausal women. - Its structure is derived from **nortestosterone**, making it a synthetic compound rather than naturally occurring. *Natural steroidal hormone* - Natural steroidal hormones like **estrogen** and **progesterone** are produced endogenously by the body and have specific steroidal molecular structures. - Tibolone is not a naturally occurring hormone but is manufactured in a lab. *Natural non-steroidal hormone* - Natural non-steroidal hormones typically include peptides (e.g., insulin) or amines (e.g., thyroid hormones). - Tibolone's chemical structure is clearly steroidal, not non-steroidal. *Synthetic non-steroidal hormone* - Synthetic non-steroidal hormones are compounds like **diethylstilbestrol** (DES) that mimic hormone action but lack the steroid nucleus. - Tibolone possesses a distinct steroid backbone, classifying it as a synthetic steroid.

Q: Which of the following is used in the second-line management of strychnine poisoning?

Barbiturates. ***Barbiturates*** - As a **second-line treatment**, barbiturates like phenobarbital are used to control **refractory seizures** and muscle spasms in strychnine poisoning when benzodiazepines are insufficient. - They enhance the effect of **GABA**, leading to central nervous system depression and muscle relaxation. *Physostigmine* - This is an **acetylcholinesterase inhibitor** and is primarily used to reverse the anticholinergic effects of certain poisonings, not strychnine. - It would worsen seizures by increasing **acetylcholine**, which can cause tremors and convulsions. *Naloxone* - Naloxone is an **opioid antagonist** used to reverse opioid overdose, which presents with respiratory depression and pinpoint pupils. - It has no role in treating strychnine poisoning, which primarily causes **muscle spasms** and seizures. *Diazepam* - Diazepam, a **benzodiazepine**, is the **first-line treatment** for seizures and muscle spasms in strychnine poisoning. - It works by enhancing the effects of **GABA** at the GABA-A receptor, thereby reducing neuronal excitability.

Question 1

The tensor veli palatini muscle is innervated by which nerve?

Accepted Answer

Mandibular nerve

Answer

Facial nerve

Answer

Vagus nerve

Answer

Glossopharyngeal nerve

Question 2

Which of the following is true about cadaveric spasm?

Accepted Answer

Some particular group of muscles are involved

Answer

Occurs 2-3 h after death

Answer

Involves involuntary muscles

Answer

Disappears with rigor mortis

Question 3

Marshall's triad is seen in:

Accepted Answer

Explosive injury

Answer

Lightning injury

Answer

Gunshot injury

Answer

Drowning injury

Question 4

Contributory negligence is negligence due to:

Accepted Answer

Patient only

Answer

Doctor only

Answer

Both doctor and patient

Answer

Hospital administrator and doctor

Question 5

Barium carbonate poisoning causes -

Accepted Answer

Muscular weakness

Answer

Gastrointestinal irritation

Answer

Cyanosis

Answer

Respiratory distress

Question 6

In sexual assault of a child, the hymen is usually not ruptured due to:

Accepted Answer

Deep seated

Answer

Distensible

Answer

Too tough to rupture

Answer

Underdeveloped

Question 7

An 18-year-old girl presents with watery diarrhea. Most likely causative agent -

Accepted Answer

V. cholerae

Answer

Rotavirus

Answer

Salmonella

Answer

Shigella

Question 8

Lendrum's stain is done for:

Accepted Answer

Amniotic fluid embolism

Answer

Air embolism

Answer

Pulmonary embolism

Answer

Fat embolism

Question 9

Tibolone is a ?

Accepted Answer

Synthetic steroid hormone

Answer

Natural steroidal hormone

Answer

Natural non-steroidal hormone

Answer

Synthetic non-steroidal hormone

Question 10

Which of the following is used in the second-line management of strychnine poisoning?

Accepted Answer

Barbiturates

Answer

Physostigmine

Answer

Naloxone

Answer

Diazepam

NEET-PG 2012

Anatomy

Forensic Medicine

Microbiology

Pathology

Pharmacology