INI-CET 2025 — Forensic Medicine
8 Previous Year Questions with Answers & Explanations
As per the MTP (Amendment) Act, 2021, the opinion of two registered medical practitioners is required for termination of pregnancy at which gestational age?
Match the following substances with their type of poisoning: Substance: A. Lead B. Croton C. Opium D. Cocaine Type of Poisoning: 1. Metallic irritant 2. Organic irritant 3. CNS depressant 4. Deliriant
In a suspected case of poisoning, gastric lavage fluid combined with silver nitrate solution gives rise to a black color in which poisoning?
Which X-ray is used to prove that an individual is more than 18 years of age?
As per Bharatiya Nyaya Sanhita (BNS), which of the following is not classified as grievous hurt?
In which of the following poisonings does silver nitrate impregnated filter paper turn black when exposed to gastric lavage contents?
The triad of abrasions, bruises and punctate lacerations are typically seen in:
One of the following statements regarding venom is incorrect:
INI-CET 2025 - Forensic Medicine INI-CET Practice Questions and MCQs
Question 1: As per the MTP (Amendment) Act, 2021, the opinion of two registered medical practitioners is required for termination of pregnancy at which gestational age?
- A. 16-20 weeks
- B. 20-24 weeks (Correct Answer)
- C. Up to 12 weeks
- D. 12-16 weeks
Explanation: The **MTP (Amendment) Act, 2021** introduced significant changes to the gestational limits and the number of medical opinions required for legal abortions in India. ### **Why Option B is Correct** Under the 2021 Amendment, the requirement for medical opinions is categorized by gestational age: * **20-24 weeks:** The opinion of **two Registered Medical Practitioners (RMPs)** is mandatory. This category is reserved for specific groups (e.g., rape survivors, minors, women with disabilities, or change in marital status). * **Beyond 24 weeks:** Termination is permitted only for **substantial fetal abnormalities**, as determined by a four-member **State-level Medical Board**. ### **Analysis of Incorrect Options** * **Option C (Up to 12 weeks) & Option D (12-16 weeks):** Under the new Act, for any pregnancy **up to 20 weeks**, the opinion of only **one RMP** is required. Previously (1971 Act), two opinions were needed between 12-20 weeks, but this was simplified in 2021. * **Option A (16-20 weeks):** Falls under the "up to 20 weeks" bracket, requiring only one RMP. ### **High-Yield Clinical Pearls for INI-CET** * **Upper Limit Extension:** The general limit for MTP was increased from 20 to **24 weeks** for special categories of women. * **Confidentiality:** Breach of a woman’s privacy regarding MTP is punishable by up to **1 year of imprisonment** and/or a fine. * **Failure of Contraception:** MTP is legal for "failure of contraception" for **both married and unmarried women** (previously only married). * **Medical Board:** Consists of a Gynaecologist, Paediatrician, Radiologist/Sonologist, and other members notified by the State Government.
Question 2: Match the following substances with their type of poisoning: Substance: A. Lead B. Croton C. Opium D. Cocaine Type of Poisoning: 1. Metallic irritant 2. Organic irritant 3. CNS depressant 4. Deliriant
- A. A-2, B-1, C-3, D-4
- B. A-1, B-2, C-3, D-4 (Correct Answer)
- C. A-4, B-3, C-2, D-1
- D. A-3, B-4, C-1, D-2
Explanation: ### **Explanation** The classification of poisons is based on their primary pharmacological action and the organ systems they target. This question tests your ability to categorize common toxicological agents. * **A-1: Lead (Metallic Irritant):** Lead is a heavy metal. In toxicology, metals like **Lead, Arsenic, Mercury, and Antimony** are classified as **Metallic Irritants** because they cause irritation and inflammation of the gastrointestinal tract and other tissues. * **B-2: Croton (Organic Irritant):** Croton (*Croton tiglium*) is a plant-based substance. Since it is derived from a living organism (plant), it is an **Organic Irritant**. Other examples include Castor seeds and Calotropis. * **C-3: Opium (CNS Depressant):** Opium and its derivatives (morphine, heroin) act on opioid receptors in the brain to slow down central nervous system activity, leading to sedation, respiratory depression, and miosis. * **D-4: Cocaine (Deliriant/Stimulant):** While Cocaine is primarily a CNS stimulant, in the context of forensic classification, it is often grouped with **Deliriants** (like Dhatura and Atropine) because toxic doses produce hallucinations, agitation, and clouded consciousness. --- ### **Why Other Options are Incorrect** * **Option A, C, & D:** These options misalign the chemical nature of the substance with its physiological effect. For example, Lead cannot be an organic irritant (it is inorganic), and Opium is never a deliriant (it causes "narcosis" or stupor, not active delirium). --- ### **High-Yield Clinical Pearls for INI-CET** * **Lead Poisoning (Plumbism):** Look for **Basophilic stippling** on blood smear and **Burtonian lines** (blue-black line) on gums. * **Croton Oil:** Known as the "Smallest dose, biggest effect" purgative; it is highly vesicant (causes blisters). * **Opium Triad:** Coma, Pin-point pupil, and Depressed respiration. * **Cocaine:** Known as the "Magnan’s Symptom" (feeling of insects crawling under the skin/formication). It is the only drug that is both a **local anesthetic and a vasoconstrictor**.
Question 3: In a suspected case of poisoning, gastric lavage fluid combined with silver nitrate solution gives rise to a black color in which poisoning?
- A. Cocaine poisoning
- B. Organophosphorus poisoning
- C. Aluminium phosphide poisoning (Correct Answer)
- D. Opium poisoning
Explanation: ### **Explanation: Silver Nitrate Test in Poisoning** The correct answer is **Aluminium phosphide poisoning**. #### **Mechanism of Action** Aluminium phosphide (Celphos), when it comes into contact with moisture or gastric acid (HCl), releases **Phosphine gas ($PH_3$)**. This gas is highly toxic and acts as a potent mitochondrial poison. The **Silver Nitrate ($AgNO_3$) Test** is a bedside diagnostic tool used to detect phosphine gas: * When gastric lavage fluid or exhaled breath containing phosphine reacts with silver nitrate, it reduces the silver ions to **metallic silver**. * This chemical reaction results in a characteristic **black color** (or dark grey precipitate). * **Chemical Reaction:** $PH_3 + 6AgNO_3 + 3H_2O \rightarrow 6Ag \text{ (Black)} + H_3PO_3 + 6HNO_3$. --- #### **Analysis of Incorrect Options** * **A. Cocaine poisoning:** Diagnosis is primarily clinical (sympathomimetic toxidrome) and confirmed via urine toxicology for metabolites like benzoylecgonine. * **B. Organophosphorus (OP) poisoning:** While OP compounds also cause a "garlicky" odor like phosphine, they do not react with silver nitrate. Diagnosis is based on **cholinergic symptoms** (miosis, salivation) and low **pseudocholinesterase** levels. * **C. Opium poisoning:** Diagnosis is based on the classic triad of **pinpoint pupils, respiratory depression, and coma**. It does not produce gases that react with silver nitrate. --- #### **High-Yield Clinical Pearls for INI-CET** * **Garlic-like odor:** Characteristic of both Phosphorus/Aluminium Phosphide and Organophosphorus poisoning. * **Mortality:** Aluminium phosphide has a very high mortality rate due to **refractory shock** and **cardiac arrhythmias**. * **Management:** There is no specific antidote. Treatment is supportive, often involving **magnesium sulphate** (for membrane stabilization) and soda bicarbonate. * **The "Silver Nitrate Paper Test":** Can also be done by placing a filter paper soaked in $AgNO_3$ over the mouth of the gastric aspirate container; a blackening of the paper confirms the presence of phosphine.
Question 4: Which X-ray is used to prove that an individual is more than 18 years of age?
- A. Appearance of inner end of clavicle, knee joint, and wrist joint
- B. Medial end of clavicle and skull
- C. Fusion of ischial tuberosity and lower end of humerus
- D. Medial end of clavicle and sternum (Correct Answer)
Explanation: ### **Explanation** In forensic age estimation, the **medial (inner) end of the clavicle** is the most reliable skeletal marker for determining if an individual has crossed the **18 to 21-year** threshold. **1. Why Option D is Correct:** * **Medial end of Clavicle:** This is the **last epiphysis** in the human body to ossify and fuse. The ossific center appears between 18–21 years and typically fuses with the shaft between **21–25 years**. Therefore, if the medial end is fused, the person is definitely over 18. * **Sternum:** The fusion of the **Xiphoid process** with the body of the sternum occurs around **40 years**, while the fusion of the segments of the body (sternebrae) occurs by age 25. These are used for older age groups. **2. Why Other Options are Incorrect:** * **Option A & C:** The **Wrist joint** (lower end of radius/ulna), **Knee joint** (lower end of femur/upper end of tibia), and **Humerus** (lower end) all typically fuse by **16–18 years**. They are used to prove an individual is a "minor" (under 18) rather than confirming they are over 18. * **Option B:** While the medial end of the clavicle is correct, the **Skull** is unreliable for precise age estimation in young adults. Suture closure (e.g., Sagittal suture) begins only after **25–30 years**. --- ### **High-Yield Clinical Pearls for INI-CET** * **Rule of 2:** The medial end of the clavicle appears at **18-21** and fuses at **21-25**. * **Most reliable bone for age:** Teeth (in children); Pelvis/Clavicle (in young adults). * **Gustafson’s Method:** Used for age estimation from teeth in adults (above 21 years) based on 6 parameters (e.g., Secondary dentin, Cementum apposition). * **Legal Significance:** 18 years is the "Age of Majority" in India; hence, the medial end of the clavicle is frequently used in medico-legal cases involving criminal responsibility and marriage legality.
Question 5: As per Bharatiya Nyaya Sanhita (BNS), which of the following is not classified as grievous hurt?
- A. Emasculation
- B. Severe body pain for 5 days (Correct Answer)
- C. Dislocation of elbow
- D. Loss of a member
Explanation: ### Explanation: Grievous Hurt under BNS Under the **Bharatiya Nyaya Sanhita (BNS)**, the definition of **Grievous Hurt** is provided in **Section 114** (which corresponds to the erstwhile Section 320 of the IPC). The criteria for an injury to be classified as "grievous" are specific and legalistic. #### Why Option B is Correct: **Severe body pain for 5 days** does not meet the legal threshold. According to the **8th clause** of Section 114 BNS, any hurt which endangers life or which causes the sufferer to be in **severe bodily pain** or unable to follow his ordinary pursuits must last for a minimum period of **20 days** to be classified as grievous hurt. Since the duration here is only 5 days, it is classified as **Simple Hurt**. #### Analysis of Incorrect Options: * **A. Emasculation:** This is the **1st clause** of grievous hurt. it refers to the depriving of a male of his masculine vigor (impotency). * **C. Dislocation of elbow:** Under the **6th clause**, any fracture or **dislocation of a bone or tooth** is considered grievous hurt, regardless of the healing time. * **D. Loss of a member:** Under the **3rd clause**, the permanent privation (loss) of any **member or joint** is classified as grievous hurt. --- ### High-Yield Clinical Pearls for INI-CET: * **BNS Section 114:** Replaces IPC 320. The 8 clauses defining grievous hurt remain essentially the same. * **The "20-Day Rule":** This is a frequent exam favorite. If a patient is hospitalized or in pain for **19 days**, it is simple hurt; **20 days or more** makes it grievous. * **Fractures:** Even a small crack in a bone (fissured fracture) or a subluxation of a tooth is **Grievous Hurt**, even if it heals in less than 20 days. * **Permanent Disfiguration:** Permanent scarring of the **face (4th clause)** or **head (5th clause)** is grievous hurt. This is often tested in cases of acid attacks or deep lacerations.
Question 6: In which of the following poisonings does silver nitrate impregnated filter paper turn black when exposed to gastric lavage contents?
- A. Malathion
- B. Opium
- C. Barbiturates
- D. Aluminium phosphide (Correct Answer)
Explanation: ***Aluminium phosphide*** - Aluminium phosphide ($AlP$) reacts vigorously with water or gastric acid to release highly toxic **phosphine gas** ($PH_3$). - Phosphine gas is a strong reducing agent that reacts with **silver nitrate ($AgNO_3$)** impregnated paper, reducing it to black **metallic silver ($Ag$)** and thus turning the paper black, a method known as the field test for Celphos. ***Malathion*** - Malathion is an **organophosphate insecticide**, and its poisoning is diagnosed primarily by clinical features of cholinergic crisis (SLUDGE syndrome) and measuring depressed **serum/RBC cholinesterase levels**. - Organophosphates do not release phosphine gas and therefore do not produce a positive reaction with silver nitrate filter paper. ***Barbiturates*** - Barbiturate poisoning is confirmed using tests like the **Dille-Koppanyi test** (for color change) or advanced **chromatographic methods** on blood or urine samples. - The barbiturate structure does not produce a reducing gas like phosphine upon reaction, so the silver nitrate paper test would remain negative. ***Opium*** - Opium poisoning (due to alkaloids like **morphine**) is confirmed by detecting the drug or its metabolites in urine or blood using **immunoassays** or gas/liquid chromatography. - Opium alkaloids are not detected by this specific qualitative test, as it is designed to detect the highly reducing nature of phosphine gas.
Question 7: The triad of abrasions, bruises and punctate lacerations are typically seen in:
- A. Road traffic accidents (Correct Answer)
- B. Fall from height
- C. Firearm injuries
- D. Bomb blast injuries
Explanation: ***Correct: Road traffic accidents*** - This specific combination of injuries—**abrasions** (due to sliding/friction), **bruises** (due to blunt force), and **punctate lacerations** (often caused by glass, debris, or gravel impacts)—is highly characteristic of **Road Traffic Accidents (RTAs)**. - These injuries reflect the simultaneous interplay of both **blunt impact** and **shearing/grinding forces** sustained as the body strikes the vehicle interior or the external road surface. - The **triad** is a classic forensic finding that distinguishes RTAs from other patterns of traumatic injury. *Incorrect: Fall from height* - Injuries from a fall are typically dominated by **high-energy blunt trauma** resulting in internal organ damage and severe skeletal fractures, such as bilateral calcaneal or vertebral fractures. - While abrasions and bruises are present at points of impact, the organized triad including numerous small, **punctate lacerations** is less distinct than in RTAs. *Incorrect: Bomb blast injuries* - Blast injuries are primarily categorized by specific mechanisms: primary (barotrauma), secondary (penetrating injuries from flying fragments), and tertiary (blunt force from body displacement). - The dominant findings are **severe organ damage** (like blast lung) and penetrating injuries; while trauma occurs, the described superficial triad is not the main characteristic pattern. *Incorrect: Firearm injuries* - Forensic examination of firearm injuries focuses on the **entry and exit wounds**, which are typically perforating or penetrating defects. - Characteristic features include the **abrasion collar**, contusion ring, and presence of GSR residue (soot or tattooing), rather than a diffuse superficial triad across multiple body areas.
Question 8: One of the following statements regarding venom is incorrect:
- A. Viperidae - Hemotoxic
- B. Elapidae - Myotoxic (Correct Answer)
- C. Common krait - Neurotoxic
- D. Common cobra - Neurotoxic
Explanation: ***Elapidae - Myotoxic*** - This statement is **incorrect**. Venom from the **Elapidae** family (e.g., cobras, kraits, mambas) is **predominantly neurotoxic**, affecting the nervous system and causing paralysis. - The primary target of Elapidae venom is the **neuromuscular junction**, leading to respiratory failure, not muscle degeneration (myotoxicity). - While some Elapidae subspecies (certain sea snakes, Australian elapids) may have myotoxic components, the family is **classically characterized as neurotoxic**, especially in the Indian context where cobras and kraits are the main representatives. ***Common cobra - Neurotoxic*** - This statement is **correct**. The venom of the **Common Cobra** (Naja naja), which belongs to the Elapidae family, is highly **neurotoxic**. - It primarily contains long and short-chain neurotoxins that cause rapid, progressive **paralysis** and respiratory failure. ***Common krait - Neurotoxic*** - This statement is **correct**. **Common Krait** (Bungarus caeruleus), also an Elapid, possesses venom that is highly potent and entirely **neurotoxic**. - Krait venom often causes severe, often delayed, **neuromuscular blockade** and paralysis, making it one of the most dangerous snakes in India. ***Viperidae - Hemotoxic*** - This statement is **correct**. Venom from the **Viperidae** family (e.g., Russell's viper, saw-scaled viper) is mainly **hemotoxic** and **cytotoxic**. - It primarily targets the blood and vascular system, causing coagulopathy, massive tissue necrosis, bleeding disorders, and often **disseminated intravascular coagulation (DIC)**.