NEET-PG 2013 - Forensic Medicine Practice Questions

Q: Stellate wound is produced with firearm in:

Contact shot. ***Contact shot*** - In a **contact shot**, gases and matter from the gun barrel are forced directly into the wound, causing the skin to stretch, tear, and burst outward, creating a **stellate or star-shaped wound**. - The hot gases and unburnt powder entering the wound create an exit for themselves, often leading to these characteristic irregular, radiating tears. *Close shot* - A close shot involves the skin being close to the muzzle but not directly touching, leading to a circular or oval wound with a surrounding area of **singeing**, **soot deposition**, and **powder tattooing**. - While there is gas effect, it's not as confined or forceful behind the skin as in a contact shot, thus not typically producing a stellate wound. *Distant shot* - A distant shot occurs when the muzzle is far enough from the target surface that only the **bullet strikes the skin**, leaving a relatively clean, circular or oval entry wound without significant singeing or tattooing. - The effects of gas and unburnt powder are not present at the wound site in a distant shot. *Range within 60 cm* - While a range within 60 cm (approximately 2 feet) can encompass close shots, it's a broad category and doesn't specifically define the conditions necessary for a stellate wound. - A stellate wound requires conditions more specific to a contact shot, where the muzzle is pressed against the skin.

Q: Acts both as poison and antidote:

Copper sulfate. ***Copper sulfate*** - **Copper sulfate** acts both as a **poison and antidote**, demonstrating dual properties. - In **large doses**, it is toxic, causing **gastrointestinal distress**, **hepatotoxicity**, **nephrotoxicity**, and potentially death. - Historically, it was used in **small controlled doses as an emetic** (to induce vomiting) in cases of poisoning, acting as an antidote by expelling ingested toxins. - **Note**: Its use as an emetic is now **outdated** due to safety concerns, but it remains the classic example of a substance with both toxic and therapeutic properties. *Mercuric chloride* - **Mercuric chloride** is a highly toxic compound acting primarily as a **corrosive poison**, causing severe damage to the **gastrointestinal tract** and kidneys. - It does not possess any antidote properties and requires aggressive **chelation therapy** for treatment. *Silver chloride* - **Silver chloride** is of **low toxicity** due to its insolubility in water and biological fluids. - While chronic exposure can cause **argyria** (bluish skin discoloration), it has no antidote properties. *Thallium arsenate* - **Thallium arsenate** contains two highly toxic elements (**thallium** and **arsenic**), both potent poisons affecting multiple organ systems. - Used in **pesticides** and **rodenticides** due to its toxicity, it has no beneficial or antidote properties.

Q: For DNA test, liquid blood is preserved in:

EDTA. ***EDTA*** - Ethylenediaminetetraacetic acid (EDTA) is the preferred anticoagulant for DNA extraction because it **chelates metal ions** (like magnesium), which are cofactors for **DNases** (enzymes that degrade DNA). - By inhibiting DNases, EDTA effectively **preserves DNA integrity** in blood samples for genetic testing. *Sodium fluoride* - **Sodium fluoride** is primarily used as an antiglycolytic agent to preserve glucose in blood samples. - It does not specifically function to preserve DNA or inhibit DNA degradation significantly. *Potassium oxalate* - **Potassium oxalate** acts as an anticoagulant by precipitating calcium, but it is not optimal for long-term DNA preservation. - Its anticoagulant properties are less suitable for molecular testing compared to EDTA, and it doesn't protect DNA as effectively. *Sodium citrate* - **Sodium citrate** is an anticoagulant primarily used for coagulation studies (e.g., PT, PTT) by chelating calcium. - While it prevents clotting, it is **less effective than EDTA** in protecting DNA from degradation by DNases, making it a poorer choice for DNA banking.

Q: Hydrostatic test (Reygate's test) for lungs is based on:

Specific gravity of lung. ***Specific gravity of lung*** - The hydrostatic test (also known as **Reygate's test** or **flotation test**) is a forensic test used to determine if a lung has ever respired, based on its **buoyancy in water**. - This buoyancy is directly related to the lung's **specific gravity**, which changes significantly depending on whether it contains air. - Aerated lungs (which have breathed) have a specific gravity less than 1 and will **float**, while non-aerated lungs have a specific gravity greater than 1 and will **sink**. *Consistency of lung* - While lung consistency can vary based on pathology, it is not the primary principle underlying the hydrostatic test. - The test specifically exploits changes in **density**, not just feel or firmness. *Volume of lungs* - Lung volume is a factor influencing buoyancy, but it's the **ratio of mass to volume** (density/specific gravity) that determines if the lung floats. - A larger lung may still sink if it is collapsed and airless, demonstrating that volume alone is not the sole basis. *Weight of lung* - The weight of the lung is important in determining its overall mass, but the hydrostatic test relies on the **weight relative to its volume** (i.e., specific gravity). - A heavy lung can still float if it contains sufficient air to lower its specific gravity below that of water.

Q: Green colored urine is seen after ingestion of:

Phenol. ***Phenol*** - Ingestion of **phenol** can lead to green-colored urine due to the formation of oxidation products, such as **hydroquinone** and **catechol**, which are excreted in the urine. - The green discoloration is a distinct toxicological sign associated with systemic phenol absorption. *Organophosphorus* - **Organophosphorus** poisoning primarily causes cholinergic symptoms like miosis, bradycardia, bronchorrhea, and muscle fasciculations. - It does not typically lead to a change in urine color; the urine usually remains clear or amber. *Copper sulphate* - **Copper sulfate** poisoning can cause symptoms like vomiting, abdominal pain, diarrhea, and potentially kidney damage. - While it can cause renal dysfunction, it does not typically result in green urine discoloration. *Cyanide* - **Cyanide** poisoning is characterized by rapid onset of symptoms affecting the cardiovascular, respiratory, and central nervous systems, leading to cellular hypoxia. - Urine color is not a characteristic feature of cyanide poisoning; it usually remains normal or slightly discolored due to other complications like rhabdomyolysis in severe cases.

Q: Yellow discoloration of skin and mucosa is seen in poisoning with:

Nitric acid. ***Nitric acid*** - **Nitric acid** causes a characteristic **yellow discoloration** of the skin and mucous membranes due to the formation of **xanthoproteic acid**. - This reaction occurs when nitric acid comes into contact with proteins, nitrating the aromatic amino acids (tyrosine, tryptophan, and phenylalanine). *Phosphoric acid* - **Phosphoric acid** burns, if severe, can cause skin irritation with redness and blistering, but typically do not result in a distinct yellow discoloration. - While corrosive, its mechanism of tissue damage differs from nitric acid's specific reaction with proteins. *Sulphuric acid* - **Sulphuric acid** is a potent dehydrating agent and corrosive acid that causes severe burns, often appearing **black or brown (eschar)** due to tissue coagulation and carbonization. - It does not produce the specific yellow discoloration seen with nitric acid. *Nitrous oxide* - **Nitrous oxide** is an inhalational anesthetic and analgesic, and its overdose can lead to **hypoxia**, dizziness, and potential bone marrow suppression with chronic abuse. - It does not cause any form of skin or mucosal discoloration; its effects are systemic and neurological.

Q: According to JJ Act 2000, a juvenile is a boy and girl respectively less than:

18 and 18. ***18 and 18*** - As per the **Juvenile Justice (Care and Protection of Children) Act, 2000**, a juvenile (or child) is defined uniformly as an individual who has not completed 18 years of age, regardless of gender. - This definition ensures that both boys and girls under 18 years old receive the same protections and care under the juvenile justice system. *16 and 18* - This option reflects an outdated or incorrect understanding of the **Juvenile Justice Act, 2000**, which specifically establishes a single age limit for both genders. - Prior to the 2000 Act and its subsequent amendments, some laws might have had different age limits for boys and girls, but the JJ Act 2000 unified this to 18 for both. *14 and 16* - This option refers to age limits that are significantly lower than those established by the **Juvenile Justice Act, 2000**, which aims to protect individuals up to the age of 18. - These ages do not correspond to the legal definition of a juvenile under the specified Act. *18 and 21* - While 18 is the correct upper age limit for both boys and girls under the **Juvenile Justice Act, 2000**, the age of 21 is typically associated with the legal age of adulthood for certain rights and responsibilities, not for defining a juvenile under this act. - The JJ Act focuses on protecting children up to 18, not distinguishing adulthood beyond that for juvenile purposes.

Q: Lathi can cause all of the following injuries, except:

Abrasion collar. ***Abrasion collar*** - An **abrasion collar** is a specific injury pattern seen exclusively in **gunshot wounds**, caused by the friction and heat of the bullet as it enters the skin - This creates a rim of abraded skin around the entry wound, which is pathognomonic for firearm injuries - A **lathi** (stick or baton) is a blunt force object and **cannot produce** this type of wound pattern *Contusion* - A **contusion** (bruise) is a classic injury from blunt force trauma - A lathi strike commonly causes contusions by rupturing small blood vessels beneath intact skin - This results in hemorrhage into soft tissues without breaking the skin surface *Incised looking lacerated wound* - While a **lathi** is a blunt object, when struck with significant force or at a tangential angle, it can cause **lacerations** that may appear incised - The tearing of skin over bony prominences can create wounds with relatively clean, straight edges - These "incised-looking" lacerations result from skin being crushed and split, mimicking cut wounds *Fissured fracture* - A **lathi** struck with sufficient force can cause **fissured fractures** - linear cracks in bone without significant displacement - This type of fracture commonly occurs in skull bones when struck by cylindrical blunt objects - The impact delivers concentrated force along a line, creating characteristic linear fracture patterns

Q: Organs first to be injured in air blast:

Ear, lung. ***Ear, lung*** - The **ear** and **lungs** are the first organs injured in an air blast due to their high air-tissue interfaces, making them extremely vulnerable to sudden pressure changes. - The **tympanic membrane** in the ear is very sensitive to barotrauma, and the **alveoli** in the lungs can rupture easily. *Pancreas, duodenum* - These organs are located deep within the abdomen and are primarily protected by other structures, making them less susceptible to direct **blast overpressure** injury. - Injuries to these organs are more typical of **secondary or tertiary blast injuries**, such as blunt trauma from impact or penetrating trauma from fragments. *Liver, muscle* - The **liver** is a solid organ that is relatively resistant to direct blast overpressure, though it can be damaged by crushing forces. - **Muscle tissue** is also dense and less vulnerable to direct air blast effects compared to air-filled organs. *Kidney, spleen* - Similar to the liver, the **kidneys** and **spleen** are solid, dense organs that are less susceptible to direct **primary blast injury**. - Injuries to these organs typically occur from **secondary or tertiary blast mechanisms**, like penetrating trauma or blunt force.

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

Question 1

Stellate wound is produced with firearm in:

Accepted Answer

Contact shot

Answer

Close shot

Answer

Distant shot

Answer

Range within 60 cm

Question 2

Acts both as poison and antidote:

Accepted Answer

Copper sulfate

Answer

Mercuric chloride

Answer

Silver chloride

Answer

Thallium arsenate

Question 3

For DNA test, liquid blood is preserved in:

Accepted Answer

EDTA

Answer

Sodium fluoride

Answer

Potassium oxalate

Answer

Sodium citrate

Question 4

Hydrostatic test (Reygate's test) for lungs is based on:

Accepted Answer

Specific gravity of lung

Answer

Consistency of lung

Answer

Volume of lungs

Answer

Weight of lung

Question 5

Green colored urine is seen after ingestion of:

Accepted Answer

Phenol

Answer

Organophosphorus

Answer

Copper sulphate

Answer

Cyanide

Question 6

Yellow discoloration of skin and mucosa is seen in poisoning with:

Accepted Answer

Nitric acid

Answer

Phosphoric acid

Answer

Sulphuric acid

Answer

Nitrous oxide

Question 7

According to JJ Act 2000, a juvenile is a boy and girl respectively less than:

Accepted Answer

18 and 18

Answer

16 and 18

Answer

14 and 16

Answer

18 and 21

Question 8

Lathi can cause all of the following injuries, except:

Accepted Answer

Abrasion collar

Answer

Contusion

Answer

Incised looking lacerated wound

Answer

Fissured fracture

Question 9

Organs first to be injured in air blast:

Accepted Answer

Ear, lung

Answer

Pancreas, duodenum

Answer

Liver, muscle

Answer

Kidney, spleen

Question 10

Barium carbonate poisoning causes -

Accepted Answer

Muscular weakness

Answer

Gastrointestinal irritation

Answer

Cyanosis

Answer

Respiratory distress

NEET-PG 2013 — Forensic Medicine