Biochemistry
2 questionsWhat is the major source of cyanocobalamin (vitamin B12)?
Replacing alanine by which amino acid, will increase UV absorbance of protein at 280 nm wavelength?
NEET-PG 2020 - Biochemistry NEET-PG Practice Questions and MCQs
Question 321: What is the major source of cyanocobalamin (vitamin B12)?
- A. Sunlight
- B. Plant-only diet
- C. Animal-only diet (Correct Answer)
- D. None of the options
Explanation: ***Animal-only diet*** - **Cyanocobalamin (vitamin B12)** is primarily found in **animal products** such as meat, fish, poultry, eggs, and dairy. - It is synthesized by microorganisms and accumulates in animal tissues, making animal-derived foods the most reliable dietary source for humans. *Sunlight* - **Sunlight** is the primary source of **vitamin D** synthesis in the skin, not vitamin B12. - Exposure to UV radiation from the sun does not contribute to the production or uptake of cyanocobalamin. *Plant-only diet* - A **plant-only diet (vegan diet)** is deficient in naturally occurring **vitamin B12**, as plants do not synthesize this vitamin. - Vegans often require **fortified foods** or **supplements** to meet their B12 needs. *None of the options* - This option is incorrect because an **animal-only diet** is identified as a major source of cyanocobalamin. - The question has a correct answer among the provided choices.
Question 322: Replacing alanine by which amino acid, will increase UV absorbance of protein at 280 nm wavelength?
- A. Glycine
- B. Tryptophan (Correct Answer)
- C. Arginine
- D. Lysine
Explanation: ***Tryptophan*** - **Tryptophan** contains an **indole ring**, which is a **chromophore** that strongly absorbs UV light at 280 nm. - Increased tryptophan content in a protein directly correlates with a higher **UV absorbance** at this wavelength. *Glycine* - **Glycine** is the simplest amino acid, with only a **hydrogen atom** as its side chain. - It does not contain any aromatic rings or other groups that absorb UV light at 280 nm, so replacing alanine with glycine would not increase UV absorbance. *Arginine* - **Arginine** is a basic amino acid with a **guanidinium group** in its side chain. - While it has a slightly complex side chain, it does not possess any **aromatic rings** that absorb significantly at 280 nm. *Lysine* - **Lysine** is another basic amino acid with a long **aliphatic chain** and an **amino group** at the end. - Similar to arginine, lysine lacks the necessary **aromatic chromophores** to contribute to UV absorbance at 280 nm.
Community Medicine
1 questionsAccording to Sustainable Development Goal 3 (SDG 3) - 'Ensure healthy lives and promote well-being for all at all ages', what is the target for reducing the global maternal mortality ratio by 2030?
NEET-PG 2020 - Community Medicine NEET-PG Practice Questions and MCQs
Question 321: According to Sustainable Development Goal 3 (SDG 3) - 'Ensure healthy lives and promote well-being for all at all ages', what is the target for reducing the global maternal mortality ratio by 2030?
- A. 100
- B. 50
- C. 70 (Correct Answer)
- D. 90
Explanation: ***70*** - SDG 3 aims to reduce the **global maternal mortality ratio** to less than **70 per 100,000 live births** by 2030. - This target emphasizes improving maternal health outcomes worldwide and preventing deaths related to pregnancy and childbirth. *100* - While a reduction is sought, a target of 100 per 100,000 live births is **not ambitious enough** to meet the specific goal set by SDG 3. - The established global target is lower, reflecting a greater commitment to maternal health. *50* - A target of 50 per 100,000 live births would be **more ambitious** than the SDG 3 goal. - While desirable, it is not the specific, agreed-upon target for the global average under SDG 3. *90* - A target of 90 per 100,000 live births is **higher** than the established SDG 3 goal. - This value does not align with the specific global maternal mortality ratio target set for 2030.
Forensic Medicine
2 questionsWhich of the following test shows yellow needle shaped crystals of spermine picrate?
In a child who has been raped, the hymen:
NEET-PG 2020 - Forensic Medicine NEET-PG Practice Questions and MCQs
Question 321: Which of the following test shows yellow needle shaped crystals of spermine picrate?
- A. Florence test
- B. Teichmann test
- C. Takayama's test
- D. Barberio's test (Correct Answer)
Explanation: ***Barberio's test*** - Barberio's test is a **presumptive test for semen**, which detects the presence of **spermine**. - It yields characteristic **yellow, needle-shaped crystals** of **spermine picrate** upon the addition of picric acid reagent to semen. - This is the **classic finding** that distinguishes this test. *Florence test* - The Florence test is a **presumptive test for seminal fluid**, identifying the presence of **choline** and **spermine**. - It produces characteristic **dark-brown, rhombic or needle-shaped crystals** of **choline periodide** (not spermine picrate) when seminal fluid is tested with Florence's reagent (potassium iodide and iodine). *Teichmann test* - The Teichmann test is a **presumptive test for blood**, specifically detecting the presence of **hemoglobin**. - It forms characteristic **rhombic crystals of hemin (hematin hydrochloride)** when blood is heated with glacial acetic acid and a halide salt. *Takayama's test* - Takayama's test is also a **presumptive test for blood**, identifying **hemoglobin**. - It produces **pink, pyridine hemochromogen crystals** after adding a solution containing pyridine, glucose, and dilute sodium hydroxide to a bloodstain.
Question 322: In a child who has been raped, the hymen:
- A. May be perforated due to trauma. (Correct Answer)
- B. May be perforated if it were superficial.
- C. Will be intact due to its anatomical position.
- D. Will be intact because it is deep situated
Explanation: ***May be perforated due to trauma.*** - The **hymen is a delicate membrane** that can be easily torn or perforated during sexual assault, especially with forceful penetration. - While hymenal tears are a strong indicator of sexual abuse, a lack of tears does not definitively rule out assault, as the hymen can be **elastic or already have natural openings**. *May be perforated if it were superficial.* - The **depth or superficiality of the hymen** is not the primary determinant of whether it will perforate during rape. - The force and nature of penile or foreign object penetration are more significant factors than its anatomical position for perforation. *Will be intact due to its anatomical position.* - The **hymen's anatomical position near the vaginal opening** makes it vulnerable to physical trauma during sexual assault. - Due to its delicate nature, it is often among the first structures to show signs of injury from forced penetration. *Will be intact because it is deep situated* - The hymen is typically located at the **entrance of the vagina**, not deep within it, making it susceptible to injury during sexual penetration. - Its relative position means it is frequently affected by trauma associated with rape, rather than being protected by depth.
Internal Medicine
2 questionsFrontal gyrus lesion leads to?
Transplantation between identical twins-
NEET-PG 2020 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 321: Frontal gyrus lesion leads to?
- A. Nominal aphasia
- B. Akinetic mutism
- C. Wernicke's aphasia
- D. Broca's aphasia (Correct Answer)
Explanation: ***Broca's aphasia*** - A lesion in the **frontal gyrus**, specifically **Broca's area** (Brodmann areas 44 and 45), leads to Broca's aphasia [1]. - This condition is characterized by **non-fluent speech**, difficulty with articulation, and telegraphic sentences, while comprehension remains relatively intact [1]. *Nominal aphasia* - This is also known as **anomic aphasia**, characterized primarily by difficulty with **word finding** (naming objects). - It results from lesions in various cortical areas, but typically not isolated to Broca's area in the frontal gyrus. *Akinetic mutism* - This condition involves a state of **unresponsiveness** where the patient is awake but does not move or speak. - It usually results from lesions in the **cingulate gyrus**, basal ganglia, or medial frontal lobes, often bilateral, not typically a solitary frontal gyrus lesion. *Wernicke's aphasia* - Wernicke's aphasia results from damage to **Wernicke's area**, located in the **posterior superior temporal gyrus** [1]. - It is characterized by **fluent but nonsensical speech** with impaired comprehension [1].
Question 322: Transplantation between identical twins-
- A. Xenograft
- B. Autograft
- C. Isograft (Correct Answer)
- D. Allograft
Explanation: ***Isograft*** - An **isograft** refers to a transplant between **genetically identical individuals**, such as identical twins, thus minimizing immune rejection [1]. - Due to the identical genetic makeup, the recipient's immune system will not recognize the transplanted tissue as foreign, making **immunosuppression unnecessary** [1]. *Xenograft* - A **xenograft** involves transplantation of tissues or organs between **different species**, for example, from a pig to a human. - These grafts typically face severe and rapid **immune rejection** due to significant genetic differences between the donor and recipient species. *Autograft* - An **autograft** is a transplant of tissue from **one part of an individual's body to another part of the same individual**. - This type of graft has no risk of rejection as the tissue is genetically identical to the recipient's own tissue [2]. *Allograft* - An **allograft** is a transplant between **genetically non-identical individuals of the same species**, such as between two non-twin humans. - These grafts always require **immunosuppressive therapy** to prevent rejection due to genetic differences, though rejection rates vary based on HLA matching [1].
Obstetrics and Gynecology
1 questions24 yr old mother with 7 week POG presents to ANC OPD with accidental low-dose radiation exposure. What is the most appropriate immediate management?
NEET-PG 2020 - Obstetrics and Gynecology NEET-PG Practice Questions and MCQs
Question 321: 24 yr old mother with 7 week POG presents to ANC OPD with accidental low-dose radiation exposure. What is the most appropriate immediate management?
- A. Reassure and continue pregnancy (Correct Answer)
- B. Perform detailed fetal anomaly scan
- C. Advise medical termination of pregnancy
- D. Advise genetic counseling and testing
Explanation: ***Reassure and continue pregnancy*** - **Low-dose radiation exposure** (typically defined as <50 mGy) during pregnancy is generally associated with a very low risk of fetal anomalies or adverse outcomes. The patient should be reassured that the risk to the fetus is minimal. - The threshold for concern for teratogenic effects from radiation is significantly higher than a low dose, and **medical termination of pregnancy** is not indicated in such cases. - This is the most appropriate **immediate management** for accidental low-dose radiation exposure at 7 weeks gestation. *Perform detailed fetal anomaly scan* - While anomaly scans are part of routine prenatal care, performing an immediate, detailed scan solely due to **low-dose radiation exposure** at 7 weeks is not the most appropriate *immediate* management. The risk of anomalies from such exposure is extremely low and unlikely to be detectable at 7 weeks. - A more detailed scan may be considered at later gestational ages (e.g., 18-20 weeks) as part of standard care, but not as an emergency response to low-dose exposure. *Advise medical termination of pregnancy* - Medical termination is **not indicated** for accidental **low-dose radiation exposure**. Termination is only considered in cases of *extremely high* and confirmed doses (e.g., >100 mGy), which carry a significant risk of severe fetal anomalies or mortality. - Such high doses are rare in accidental exposures and would necessitate a thorough dose assessment by a radiation physicist before considering any drastic measures. - Since the scenario specifies low-dose exposure, termination would be inappropriate and potentially harmful counseling. *Advise genetic counseling and testing* - **Genetic counseling** and testing would be indicated for known genetic risks, advanced maternal age, or suspicion of chromosomal abnormalities, none of which are suggested by accidental **low-dose radiation exposure**. - Radiation-induced effects are typically teratogenic rather than directly causing inheritable genetic mutations that would be detected by standard genetic testing.
Pediatrics
1 questionsA newborn baby presented with a failure to pass meconium in the immediate postnatal period. The pediatrician also notices visible yet ineffective peristalsis, and abdominal distention. A radiological contrast enema demonstrated a narrow conical segment and a dilated proximal bowel. A diagnosis of Hirschsprung disease was made. Which of the following is a cause of the condition in the patient?
NEET-PG 2020 - Pediatrics NEET-PG Practice Questions and MCQs
Question 321: A newborn baby presented with a failure to pass meconium in the immediate postnatal period. The pediatrician also notices visible yet ineffective peristalsis, and abdominal distention. A radiological contrast enema demonstrated a narrow conical segment and a dilated proximal bowel. A diagnosis of Hirschsprung disease was made. Which of the following is a cause of the condition in the patient?
- A. Persistence of embryonic structures in the bowel wall
- B. Congenital obstruction due to external factors
- C. Failure of migration of neural crest cells (Correct Answer)
- D. Abnormal peristalsis due to neural dysfunction
Explanation: ***Failure of migration of neural crest cells*** - Hirschsprung disease is characterized by the **absence of ganglion cells** (specifically **Auerbach's and Meissner's plexuses**) in the distal bowel. - This aganglionosis results from the **failure of neural crest cells to migrate** completely into the intestinal wall during embryonic development. *Persistence of embryonic structures in the bowel wall* - This mechanism is associated with conditions like **Meckel's diverticulum**, where a remnant of the **vitelline duct** persists. - It does not explain the absence of ganglion cells or the functional obstruction seen in Hirschsprung disease. *Congenital obstruction due to external factors* - This would involve conditions such as an **annular pancreas**, **bands**, or **malrotation with volvulus**, creating a physical barrier. - Hirschsprung disease is a **functional obstruction** due to neuromuscular dysfunction, not an external compression or blockage. *Abnormal peristalsis due to neural dysfunction* - While there is abnormal peristalsis, the underlying cause is not just **"neural dysfunction"** in a general sense, but specifically the **absence of entire ganglion cell plexuses** within the bowel wall. - This option is too broad and doesn't pinpoint the precise developmental defect.
Psychiatry
1 questionsWhich of the following is a technique based on behavior sciences methods?
NEET-PG 2020 - Psychiatry NEET-PG Practice Questions and MCQs
Question 321: Which of the following is a technique based on behavior sciences methods?
- A. Systems analysis
- B. Decision making
- C. Network analysis
- D. Management by objective (Correct Answer)
Explanation: ***Management by objective*** - **Management by objective (MBO)** is a strategic management model that aims to improve organizational performance by clearly defining **objectives** that are agreed to by both management and employees. - It is based on **behavioral science principles** because it emphasizes employee participation, motivation, and goal setting to achieve desired outcomes. *Systems analysis* - **Systems analysis** is a problem-solving technique that involves breaking down a complex system into its component parts to study how they interact. - It is primarily an engineering and computer science discipline, focused on **optimizing processes** and **information flow**, rather than explicit behavioral methods. *Decision making* - **Decision making** is a cognitive process of selecting a course of action from various alternatives. - While influenced by human behavior, it is a broad concept that encompasses various analytical and intuitive approaches, and is not solely a behavior sciences method. *Network analysis* - **Network analysis** is a method for visualizing and analyzing interconnected nodes (e.g., people, organizations) and their relationships. - It is often used in **sociology, epidemiology, and computer science** to understand structures and interactions, but it is not inherently a technique based on behavioral sciences methods in the same way MBO is.