NEET-PG 2019 Practice Questions

Q: Structure derived from first pharyngeal arch:

Anterior belly of digastric. ***Anterior belly of digastric*** - The **first pharyngeal arch** (mandibular arch) gives rise to the muscles of mastication, including the **anterior belly of the digastric muscle**. Others are the **mylohyoid muscle**, and the **tensor tympani** and **tensor veli palatini muscles**. - Its nerve supply is the **mandibular nerve (V3)**, which is the nerve of the first pharyngeal arch. *Levator palatini* - The **levator palatini muscle** is derived from the **fourth pharyngeal arch**. - It is innervated by the **pharyngeal plexus**, which contains fibers from the **vagus nerve (CN X)** (nerve of the fourth arch). *Buccinator* - The **buccinator muscle** is derived from the **second pharyngeal arch** (hyoid arch). - It is innervated by the **facial nerve (CN VII)**, which is the nerve of the second pharyngeal arch. *Stylohyoid* - The **stylohyoid muscle** is derived from the **second pharyngeal arch** (hyoid arch). - It is innervated by the **facial nerve (CN VII)**, which is the nerve of the second pharyngeal arch.

Q: In Wilson’s disease, which of the following substances is excreted in lower amounts in the urine?

Methyl- Histidine. **Important Note:** In Wilson's disease with Fanconi syndrome (proximal renal tubular dysfunction), most substances show **increased** urinary excretion, not decreased. This question appears to test knowledge of what is NOT characteristically elevated. ***Methyl-Histidine*** (Most appropriate answer) - **Methyl-histidine** (3-methylhistidine) is a marker of **muscle protein breakdown** and is not directly affected by the renal tubular dysfunction in Wilson's disease - Unlike phosphate, amino acids, and glucose which are pathologically increased in urine due to Fanconi syndrome, methyl-histidine excretion remains **normal** or is unrelated to copper-induced renal damage - This represents the substance least affected by Wilson's disease pathology *Phosphorus* (Actually INCREASED, not decreased) - **Medically incorrect as stated**: Phosphorus (phosphate) is actually **INCREASED** in urine in Wilson's disease, not decreased - Fanconi syndrome causes **renal phosphate wasting**, leading to hyperphosphaturia and resultant hypophosphatemia - This is a characteristic feature of proximal tubular dysfunction *Serine* (INCREASED due to aminoaciduria) - **Serine** and other amino acids show **generalized aminoaciduria** in Wilson's disease due to impaired proximal tubular reabsorption - Urinary serine is **elevated**, not decreased *Phosphotyrosine* - A phosphorylated amino acid involved in cell signaling, not routinely measured clinically - Not characteristically implicated in Wilson's disease urinary patterns

Q: Which is the most common ocular finding in myasthenia gravis?

Ptosis. ***Ptosis*** - **Ptosis**, or drooping of the eyelid, is the most common ocular manifestation of **myasthenia gravis**, affecting a large majority of patients. - It results from **weakness of the levator palpebrae superioris muscle**, which is responsible for lifting the eyelid. *Lagophthalmos* - **Lagophthalmos** is the inability to close the eyelids completely, often due to facial nerve palsy or severe proptosis. - While it can lead to exposure keratopathy, it is **not a primary or common finding** in myasthenia gravis. *Proptosis* - **Proptosis** (or exophthalmos) is the forward bulging of the eyeball, most commonly associated with **Graves' ophthalmopathy**. - It is **not a feature of myasthenia gravis**, which typically involves muscle weakness, not orbital mass effects. *Enophthalmos* - **Enophthalmos** refers to the posterior displacement of the eyeball within the orbit, often seen in conditions like **orbital fractures** or Horner's syndrome. - It is **not associated with the neuromuscular dysfunction** characteristic of myasthenia gravis.

Q: Which one of the following is an autosomal recessive disorder?

Albinism. ***Albinism*** - **Albinism** is an **autosomal recessive disorder** characterized by a partial or complete lack of melanin pigment in the skin, hair, and eyes [1], [2]. - This condition is inherited when an individual receives **two copies of the defective gene**, one from each parent [1]. *Huntington's disease* - **Huntington's disease** is an **autosomal dominant disorder**, meaning only one copy of the mutated gene is sufficient to cause the disease. - It is characterized by progressive neurodegeneration, leading to uncontrolled movements, cognitive decline, and psychiatric problems. *Marfan's syndrome* - **Marfan's syndrome** is an **autosomal dominant disorder** affecting connective tissue, primarily impacting the skeletal, ocular, and cardiovascular systems. - It results from a mutation in the **FBN1 gene** which encodes for fibrillin-1, a component of elastic fibers. *Neurofibromatosis-1* - **Neurofibromatosis type 1 (NF1)** is an **autosomal dominant disorder** caused by a mutation in the NF1 gene, leading to the growth of tumors along nerves. - Clinical features include **café-au-lait spots**, neurofibromas, and Lisch nodules. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Genetic Disorders, pp. 150-151. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. (Basic Pathology) introduces the student to key general principles of pathology, both as a medical science and as a clinical activity with a vital role in patient care. Part 2 (Disease Mechanisms) provides fundamental knowledge about the cellular and molecular processes involved in diseases, providing the rationale for their treatment. Part 3 (Systematic Pathology) deals in detail with specific diseases, with emphasis on the clinically important aspects., pp. 119-120.

Q: The histopathological image shows a section of colon. What histological feature seen in the image is more characteristic of Ulcerative Colitis than Crohn's Disease?

Presence of crypt abscesses. ***Crypt abscess*** - **Crypt abscesses** are a hallmark of ulcerative colitis, where there is **inflammation and necrosis** within the intestinal crypts [1]. - This feature is distinct from Crohn's disease, which does not typically present with crypt abscesses but rather with **transmural inflammation** [2,3]. *Diffuse distribution of pseudopolyps* - While pseudopolyps can occur in ulcerative colitis, they are not a **distinct histological feature** that differentiates it from Crohn's. - Pseudopolyps are **proliferative tissue islands** due to mucosal regeneration, and their presence is not exclusive to either condition. *Mucosal edema* - Mucosal edema is a common feature in various forms of colitis but is **not specific** to differentiate ulcerative colitis from Crohn's disease. - Both conditions can exhibit **mucosal edema**, making it insufficient for definitive diagnosis. *Lymphoid aggregates in the mucosa* - Lymphoid aggregates can be found in Crohn's disease, particularly in the **intestinal lymphoid tissue** [2], but they are **not a defining feature** of ulcerative colitis. - Ulcerative colitis primarily involves **continuous mucosal inflammation** without these prominent aggregates [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, p. 809. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Alimentary System Disease, pp. 365-368. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 806-807.

Q: Hormone predominantly secreted after 14 days that acts on the endometrium is?

Progesterone. ***Progesterone*** - After **ovulation** (around day 14 of a typical 28-day cycle), the **corpus luteum** forms and begins secreting large amounts of progesterone. - Progesterone's primary role is to prepare the **endometrium** for potential implantation by making it secretory and vascularized. *Estrogen* - Estrogen levels are highest during the **proliferative phase** (days 1-14), promoting endometrial growth and thickening. - While present after day 14, its predominant role shifts to preparing the uterus, but not as the *main* hormone secreted to support the post-ovulatory endometrium. *LH (Luteinizing Hormone)* - LH is crucial for triggering **ovulation** itself, with a surge occurring just before day 14. - After ovulation, LH levels decrease and its primary role is not direct endometrial modification. *FSH (Follicle-Stimulating Hormone)* - FSH is primarily active in the **follicular phase** (days 1-14), stimulating ovarian follicle growth. - Its levels decrease after ovulation, and it does not directly regulate endometrial changes in the post-ovulatory period.

Q: What is the PRIMARY vascular function of PGI2 (prostacyclin)?

Inhibits platelet aggregation and causes vasodilation. ***Inhibits platelet aggregation and causes vasodilation*** - **PGI2 (prostacyclin)** is a potent **vasodilator** that relaxes smooth muscle in blood vessels, increasing blood flow. - It also effectively **inhibits platelet aggregation**, preventing the formation of blood clots. *Promotes platelet aggregation and causes vasoconstriction* - This describes the primary actions of **thromboxane A2 (TXA2)**, not PGI2. - TXA2 is produced by platelets and plays a key role in **hemostasis** by constricting blood vessels and promoting platelet clumping. *Acts primarily as a bronchoconstrictor* - While some prostaglandins can affect bronchial tone, **PGI2's primary vascular role** is vasodilation and anti-aggregation. - **Leukotrienes** and certain **prostaglandins (e.g., PGD2, PGF2α)** are more classically associated with bronchoconstriction. *Stimulates inflammatory cell chemotaxis* - This is primarily a function of other inflammatory mediators such as **leukotriene B4 (LTB4)** and **C5a anaphylatoxin**. - While other eicosanoids can indirectly influence inflammation, **PGI2's main actions** are vascular and anti-platelet.

Q: CEAP score indicates-

Venous disorder. ***Venous disorder*** - The **CEAP classification** is a widely recognized system used to categorize and describe chronic venous disorders. The acronym stands for **Clinical, Etiological, Anatomical, and Pathophysiological** factors. - It provides a standardized framework for clinicians to classify the severity and characteristics of **venous disease**, ranging from spider veins to active ulcers. *Atrial disorders* - **Atrial disorders** refer to conditions affecting the atria of the heart, such as **atrial fibrillation** or **atrial flutter**. - These are cardiovascular conditions distinct from venous disorders, which involve the veins (blood vessels returning blood to the heart). *Neurological disorder* - A **neurological disorder** is a condition affecting the **nervous system**, including the brain, spinal cord, and nerves. - The CEAP classification is specifically designed for vascular conditions and has no direct relevance to neurological diseases. *Trauma disorder* - A **trauma disorder** is a condition resulting from a **physically or psychologically traumatic event**. - While trauma can sometimes lead to venous issues (e.g., deep vein thrombosis from immobilization), the CEAP score itself is a classification system for chronic venous disease, not for traumatic conditions in general.

Q: What is the most likely diagnosis for the parotid mass with mixed consistency shown in the image?

Pleomorphic adenoma. ***Pleomorphic adenoma*** - The **mixed consistency** of the parotid mass indicates a **benign tumor**, predominantly of epithelial and mesenchymal origin, typical of pleomorphic adenomas. - This type of tumor is usually **pain-free** and can exhibit a **soft** and **firm** texture on examination [1]. *Sebaceous cyst* - Typically presents as a **smooth, fluctuant nodule** and usually has a **firm consistency** rather than mixed. - Generally not seen as a parotid mass; usually found on the skin in areas with sebaceous glands. *Dermoid cyst* - Generally presents as a **well-defined, soft, and mobile mass**, not commonly associated with mixed consistency. - Often contains **keratin** and has a more homogenous consistency rather than the mixed characteristics of pleomorphic adenoma. *All* - As not all options are suitable for the description of a **mixed consistency parotid mass**, this option is incorrect. - Only **pleomorphic adenoma** aligns with the specific clinical presentation detailed in the question [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Head and Neck, pp. 751-753.

Question 1

Structure derived from first pharyngeal arch:

Accepted Answer

Anterior belly of digastric

Answer

Levator palatini

Answer

Buccinator

Answer

Stylohyoid

Question 2

In Wilson’s disease, which of the following substances is excreted in lower amounts in the urine?

Accepted Answer

Methyl- Histidine

Answer

Phosphotyrosine

Answer

Phosphorus

Answer

Serine

Question 3

What is the primary method for diagnosing Pneumocystis jirovecii pneumonia?

Accepted Answer

Bronchoalveolar lavage (BAL)

Answer

Sputum microscopy

Answer

Chest X-ray findings

Answer

Serum beta-D-glucan assay

Question 4

Which is the most common ocular finding in myasthenia gravis?

Accepted Answer

Ptosis

Answer

Lagophthalmos

Answer

Proptosis

Answer

Enophthalmos

Question 5

Which one of the following is an autosomal recessive disorder?

Accepted Answer

Albinism

Answer

Marfan’s syndrome

Answer

Neurofibromatosis-1

Answer

Huntington's disease

Question 6

The histopathological image shows a section of colon. What histological feature seen in the image is more characteristic of Ulcerative Colitis than Crohn's Disease?

Accepted Answer

Presence of crypt abscesses

Answer

Presence of pseudopolyps

Answer

Mucosal edema present

Answer

Lymphoid aggregates in the mucosa present

Question 7

Hormone predominantly secreted after 14 days that acts on the endometrium is?

Accepted Answer

Progesterone

Answer

Estrogen

Answer

LH

Answer

FSH

Question 8

What is the PRIMARY vascular function of PGI2 (prostacyclin)?

Accepted Answer

Inhibits platelet aggregation and causes vasodilation

Answer

Promotes platelet aggregation and causes vasoconstriction

Answer

Acts primarily as a bronchoconstrictor

Answer

Stimulates inflammatory cell chemotaxis

Question 9

CEAP score indicates-

Accepted Answer

Venous disorder

Answer

Atrial disorders

Answer

Trauma disorder

Answer

Neurological disorder

Question 10

What is the most likely diagnosis for the parotid mass with mixed consistency shown in the image?

Accepted Answer

Pleomorphic adenoma

Answer

Sebaceous cyst

Answer

Dermoid cyst

Answer

None of the options

NEET-PG 2019

Anatomy

Biochemistry

Microbiology

Ophthalmology

Pathology

Physiology

Surgery