Anatomy
1 questionsTrigone of urinary bladder develops from:
NEET-PG 2015 - Anatomy NEET-PG Practice Questions and MCQs
Question 1331: Trigone of urinary bladder develops from:
- A. Ectoderm
- B. Mesoderm (Correct Answer)
- C. None of the options
- D. Endoderm of urachus
Explanation: ***Mesoderm*** - The **trigone** of the urinary bladder develops from the **distal ends of the mesonephric (Wolffian) ducts**, which are **mesodermal in origin**. - These ducts are **absorbed into the posterior wall of the bladder**, forming the smooth triangular area between the two ureteric orifices and the internal urethral orifice [1]. - Although the epithelium of the trigone is later **replaced by endodermal epithelium** from the urogenital sinus, the **structural origin remains mesodermal**. - This is a classic example of **epithelial metaplasia** where endodermal epithelium replaces mesodermal tissue. *Endoderm of urachus* - The **urachus** is the fibrous remnant of the allantois that connects the apex of the bladder to the umbilicus. - It forms the **median umbilical ligament** in adults and does **not contribute to the trigone**. - The **urogenital sinus** (endodermal) forms the majority of the bladder body, but not the trigone. *Ectoderm* - The **ectoderm** forms the nervous system, epidermis, and sensory epithelia. - It does **not contribute** to the development of the urinary bladder or its trigone. - The urinary system is derived from **mesoderm** (kidneys, ureters, trigone) and **endoderm** (bladder body, urethra). *None of the options* - This is incorrect because **mesoderm** is the correct embryological origin of the trigone. - The mesonephric ducts that form the trigone are definitively mesodermal structures.
Forensic Medicine
1 questionsDuring a postmortem examination of a young adult found with a faded tattoo, relatives mentioned that the tattoo was once visible. What is the best method to identify the tattoo?
NEET-PG 2015 - Forensic Medicine NEET-PG Practice Questions and MCQs
Question 1331: During a postmortem examination of a young adult found with a faded tattoo, relatives mentioned that the tattoo was once visible. What is the best method to identify the tattoo?
- A. Use a spectrophotometer for analysis
- B. Illuminate with ordinary light
- C. Perform an X-ray examination
- D. Illuminate with ultraviolet (UV) light (Correct Answer)
Explanation: ***Illuminate with ultraviolet (UV) light*** - **UV light** causes residual tattoo pigments, even faded ones, to **fluoresce**, making them visible again for identification. - This method is particularly effective for **older or faded tattoos** where the pigment has degraded or spread. *Use a spectrophotometer for analysis* - A spectrophotometer is used to measure the **intensity of light** as a function of wavelength, which is useful for **analyzing chemical components or color intensity**. - While it can analyze pigments, it is not the primary or most practical method for merely **identifying the presence and pattern of a faded tattoo** on skin, especially in a postmortem context. *Illuminate with ordinary light* - **Ordinary visible light** is typically insufficient to reveal tattoos that have significantly faded or been subjected to processes that obscure them. - If the tattoo is already faded to the point of being invisible to the naked eye, **ordinary light will not enhance its visibility** as it lacks the specific wavelengths needed to cause fluorescence. *Perform an X-ray examination* - **X-rays** are used to visualize dense structures like **bones and foreign bodies**, not for examining skin or pigments. - Tattoo pigments are generally **not radiopaque** and would not be visible on an X-ray film, rendering this method useless for tattoo identification.
General Medicine
1 questionsWhich of the following syndromes is least likely to be associated with obesity?
NEET-PG 2015 - General Medicine NEET-PG Practice Questions and MCQs
Question 1331: Which of the following syndromes is least likely to be associated with obesity?
- A. Cushing syndrome
- B. Prader willi syndrome
- C. Sipple syndrome (Correct Answer)
- D. Pickwickian syndrome
Explanation: ***Sipple syndrome*** - Sipple syndrome, also known as **multiple endocrine neoplasia type 2**, is primarily associated with **medullary thyroid carcinoma** and does not typically correlate with obesity. - It includes signs like **pheochromocytoma** and **hyperparathyroidism**, but obesity is not a prominent feature. *Cushing syndrome* - Cushing syndrome leads to **excess cortisol**, commonly resulting in weight gain and central obesity [1]. - Characteristic features include **moon facies**, **buffalo hump**, and easy bruising, all associated with obesity [1]. *Pickwinian syndrome* - Pickwinian syndrome, characterized by **severe obesity**, is a condition primarily affecting physical stature and weight. - It is linked to **hypoventilation** and sleep apnea, reinforcing the presence of obesity. *Prader willi syndrome* - Prader-Willi syndrome is marked by **insatiable hunger** leading to **obesity** due to hypothalamic dysfunction [2]. - Individuals with this condition also demonstrate **hypotonia** and developmental delays, commonly accompanied by obesity [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1127-1129. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Central Nervous System Synapse, pp. 454-455.
Internal Medicine
1 questionsSausage finger appearance is associated with which of the following conditions?
NEET-PG 2015 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 1331: Sausage finger appearance is associated with which of the following conditions?
- A. Rickets
- B. Hyperthyroidism
- C. Addison's disease
- D. Psoriatic arthritis (Correct Answer)
Explanation: ***Psoriatic arthritis*** - **Dactylitis**, or "sausage finger," is a characteristic inflammatory finding in psoriatic arthritis, resulting from inflammation of the **entire digit** [1]. - This condition involves inflammation of tendons, joints, and soft tissues which leads to diffuse swelling of fingers or toes [1]. *Rickets* - Rickets is a bone-softening disease in children caused by **vitamin D deficiency**, leading to bone deformities like bowed legs or widened wrists. - It does not present with inflammatory dactylitis or "sausage digits." *Hyperthyroidism* - Hyperthyroidism is a condition of excessive thyroid hormone production, which can cause symptoms like **tremors**, **tachycardia**, and **weight loss** [2]. - It is not associated with dactylitis or changes in finger morphology. *Addison's disease* - Addison's disease results from **adrenal insufficiency**, leading to symptoms like **fatigue**, **skin hyperpigmentation**, and hypotension. - There is no clinical association between Addison's disease and "sausage finger" appearance.
Microbiology
1 questionsNeutralization test is
NEET-PG 2015 - Microbiology NEET-PG Practice Questions and MCQs
Question 1331: Neutralization test is
- A. Widal test
- B. Weil-Felix test
- C. Paul-Bunnell test
- D. Nagler reaction (Correct Answer)
Explanation: ***Nagler reaction*** - The **Nagler reaction** is a biochemical test used to identify **Clostridium perfringens**, based on its ability to produce **alpha-toxin (lecithinase)**, which hydrolyzes lecithin in egg yolk agar. - It is a neutralization test because the lecithinase activity can be **inhibited (neutralized)** by antitoxin, leading to a diminished zone of opalescence or turbidity around colonies grown on egg yolk agar. *Widal test* - The **Widal test** is an **agglutination test** used to diagnose **typhoid fever** by detecting antibodies against *Salmonella typhi* O and H antigens in a patient's serum. - It measures the presence of antibodies that cause bacterial clumping, not the neutralization of a toxin. *Weil-Felix test* - The **Weil-Felix test** is an **agglutination test** used to diagnose **rickettsial infections** like epidemic typhus, scrub typhus, and Rocky Mountain spotted fever. - It detects antibodies that cross-react with specific **Proteus vulgaris** antigens, and is not a neutralization assay for toxins or enzymes. *Paul Bunnel test* - The **Paul-Bunnell test** is an **agglutination test** used to diagnose **infectious mononucleosis** by detecting heterophile antibodies that agglutinate sheep red blood cells. - It relies on the clumping of red blood cells by antibodies and does not involve the neutralization of a microbial product.
Pharmacology
2 questionsWhich of the following is the only clinically available depolarizing muscle relaxant?
Which of the following drugs is an alpha 2 agonist?
NEET-PG 2015 - Pharmacology NEET-PG Practice Questions and MCQs
Question 1331: Which of the following is the only clinically available depolarizing muscle relaxant?
- A. Decamethonium
- B. Suxamethonium (Correct Answer)
- C. Mivacurium
- D. None of the options
Explanation: ***Suxamethonium*** - **Suxamethonium** (also known as succinylcholine) is currently the **only depolarizing neuromuscular blocker** available for clinical use. - It works by mimicking acetylcholine, binding to and activating nicotinic acetylcholine receptors at the **neuromuscular junction**, causing initial muscle fasciculations followed by relaxation. *Decamethonium* - **Decamethonium** is a depolarizing neuromuscular blocker but is **no longer clinically available** due to its prolonged action and side effects. - It also acts by opening nicotinic acetylcholine receptor channels, leading to depolarization and muscle paralysis. *Mivacurium* - **Mivacurium** is a **nondepolarizing neuromuscular blocker**, meaning it acts as a competitive antagonist at the acetylcholine receptor. - It is known for its **short duration of action** due to rapid hydrolysis by plasma cholinesterases but is not depolarizing. *None of the options* - This option is incorrect because suxamethonium is indeed a clinically available depolarizing muscle relaxant. - The question specifically asks for the *only* clinically available one, which suxamethonium fulfills.
Question 1332: Which of the following drugs is an alpha 2 agonist?
- A. Apraclonidine (Correct Answer)
- B. Timolol
- C. PG analogues
- D. Verapamil
Explanation: ***Apraclonidine*** - **Apraclonidine** is a synthetic **alpha-2 adrenergic agonist** that reduces aqueous humor production and increases uveoscleral outflow, thereby lowering intraocular pressure. - It is primarily used for the short-term treatment of **open-angle glaucoma** or ocular hypertension. *Timolol* - **Timolol** is a **non-selective beta-adrenergic blocker** that reduces aqueous humor production, leading to a decrease in intraocular pressure. - It does not act on alpha-2 receptors, distinguishing it from apraclonidine. *PG analogues* - **Prostaglandin analogues** (PG analogues) such as latanoprost, bimatoprost, and travoprost are primarily used to treat glaucoma by **increasing uveoscleral outflow** of aqueous humor. - They act on **prostaglandin F2α receptors**, not alpha-2 adrenergic receptors. *Verapamil* - **Verapamil** is a **calcium channel blocker** primarily used to treat hypertension, angina, and arrhythmias. - It acts by blocking calcium channels in vascular smooth muscle and the heart, and does not have significant alpha-2 adrenergic agonist activity.
Radiology
3 questionsEpidural hematoma on CT scan shows which of the following?
Investigation of choice for soft tissue sarcoma is -
Tigroid pattern on MRI is seen in -
NEET-PG 2015 - Radiology NEET-PG Practice Questions and MCQs
Question 1331: Epidural hematoma on CT scan shows which of the following?
- A. Biconvex hyperdense lesion (Correct Answer)
- B. Crescent-shaped hyperdense lesion
- C. Biconcave hypodense lesion
- D. Ring-enhancing hypodense lesion
Explanation: ***Biconvex hyperdense lesion*** - An epidural hematoma is characterized by a **biconvex** (lens-shaped) collection of blood between the dura mater and the skull. - Since it is an acute hemorrhage, the blood appears **hyperdense** (bright white) on a CT scan. *Crescent-shaped hyperdense lesion* - A **crescent shape** is characteristic of an **acute subdural hematoma**, not an epidural hematoma. - While acute subdural hematomas are also hyperdense, their crescent shape (following the contour of the brain) distinguishes them from the biconvex epidural hematomas. - Epidural hematomas are limited by suture lines and appear lens-shaped, while subdural hematomas can cross suture lines. *Biconcave hypodense lesion* - A **biconcave** shape is not a standard description in neuroradiology and does not represent epidural hematoma. - **Hypodense** would indicate an older lesion or other pathology, not acute hemorrhage. *Ring-enhancing hypodense lesion* - **Ring-enhancing lesions** are typically associated with abscesses, glioblastoma, or metastatic tumors, not an acute hematoma. - A **hypodense** (darker) center with enhancement would indicate an abscess or necrotic tumor, not a fresh extravasation of blood.
Question 1332: Investigation of choice for soft tissue sarcoma is -
- A. CT
- B. MRI (Correct Answer)
- C. Ultrasound
- D. X-ray
Explanation: ***MRI*** - **Magnetic Resonance Imaging (MRI)** is the investigation of choice for soft tissue sarcomas due to its superior **soft tissue contrast resolution**, allowing for detailed assessment of tumor size, location, and extent within muscle, fat, and neurovascular structures. - MRI is crucial for **surgical planning**, helping to define tumor margins and evaluate involvement of adjacent critical structures. *CT* - While CT scans can identify masses, they have **limited soft tissue contrast resolution** compared to MRI, making it less effective for precise delineation of soft tissue sarcomas. - CT is often used for **staging to detect metastatic disease**, particularly in the lungs, rather than for primary tumor characterization. *Ultrasound* - **Ultrasound** is a good initial screening tool for soft tissue masses due to its accessibility and lack of radiation, but it is **operator-dependent** and has limitations in assessing deep or large lesions. - It can help differentiate cystic from solid lesions and guide biopsies but **lacks the comprehensive detail** of MRI for definitive diagnosis and staging. *X-ray* - **X-rays** are primarily used to visualize **bone abnormalities** and are generally not effective for evaluating soft tissue masses unless there is associated calcification or bone erosion. - They provide **minimal information** regarding the internal structure or extent of a soft tissue sarcoma.
Question 1333: Tigroid pattern on MRI is seen in -
- A. Wilson's disease
- B. Metachromatic leukodystrophy (Correct Answer)
- C. Parkinsonism
- D. GB syndrome
Explanation: ***Metachromatic leukodystrophy*** - The **tigroid pattern** on MRI, characterized by **perivascular sparing** within demyelinated white matter, is highly characteristic of metachromatic leukodystrophy. - This pattern results from the accumulation of **sulfatides** in oligodendrocytes and macrophages, leading to central demyelination with spared U-fibers and white matter adjacent to vessels. *Wilson's disease* - Wilson's disease involves **copper accumulation** and typically presents with abnormalities in the **basal ganglia**, thalami, and brainstem. - While it causes neurodegeneration, it does not produce a characteristic tigroid demyelination pattern. *Parkinsonism* - Parkinsonism refers to a group of neurological disorders characterized by motor symptoms like **bradykinesia, rigidity, tremor, and postural instability**. - MRI findings in Parkinsonism often show **nigral degeneration** but do not typically involve a tigroid pattern of leukodystrophy. *GB syndrome* - **Guillain-Barré syndrome (GBS)** is an acute autoimmune peripheral neuropathy affecting the **peripheral nerves and nerve roots**. - It does not involve central nervous system demyelination or display a tigroid pattern on brain MRI.