NEET-PG 2018 Practice Questions

Q: What do chaperones assist in?

Protein Folding. ***Protein Folding*** - **Chaperone proteins** bind to newly synthesized polypeptide chains and unfolded proteins, helping them achieve their **correct three-dimensional structure**. - They also prevent **misfolding** and **aggregation** of proteins, which can be detrimental to cellular function. *Protein Cleavage* - **Protein cleavage** involves the enzymatic hydrolysis of peptide bonds, often performed by **proteases**. - This process is not directly facilitated by chaperones; chaperones primarily function in structural maturation, not degradation or processing. *Protein Degradation* - **Protein degradation** is carried out by systems like the **ubiquitin-proteasome pathway** or lysosomes, which break down damaged or unwanted proteins. - While chaperones can triage misfolded proteins for degradation, they do not directly perform the degradation themselves. *Protein Modification* - **Protein modification** involves the covalent attachment of chemical groups (e.g., phosphorylation, glycosylation) or other molecules to a protein. - This process is performed by specific enzymes like kinases or glycosyltransferases; chaperones’ role is more structural than enzymatic modification.

Q: Which vitamin deficiency is associated with night blindness?

Vit. A. ***Vitamin A*** - **Vitamin A deficiency is THE classic cause of night blindness (nyctalopia)**, one of the earliest signs of deficiency - Vitamin A is essential for synthesis of **rhodopsin**, the photopigment in retinal rod cells responsible for vision in dim light - Deficiency leads to impaired dark adaptation and progressive loss of night vision - Other manifestations include **xerophthalmia, Bitot's spots, and keratomalacia** - This is a high-yield fact for NEET-PG examinations *Riboflavin (Vitamin B2)* - Riboflavin deficiency causes **oral-ocular-genital syndrome** - Clinical features include **angular stomatitis, cheilosis, glossitis, seborrheic dermatitis** - Eye manifestations include **corneal vascularization and photophobia**, NOT night blindness - Does NOT cause night blindness as a primary symptom *Thiamine (Vitamin B1)* - Thiamine deficiency causes **Beriberi** (wet and dry forms) and **Wernicke-Korsakoff syndrome** - Characterized by peripheral neuropathy, cardiac dysfunction, and CNS manifestations - Does NOT cause night blindness *Biotin (Vitamin B7)* - Biotin deficiency is rare and causes **dermatitis, alopecia, conjunctivitis** - Also causes neurological symptoms in severe deficiency - Does NOT cause night blindness

Q: Which of the following statements about keloids is MOST true?

Keloids may extend beyond the original wound.. ***Keloids may extend beyond the original wound.*** - Keloids are characterized by their **overgrowth** beyond the boundaries of the original injury. - This distinguishes them from **hypertrophic scars**, which remain confined to the wound edges. *Extended excision is often not the treatment of choice.* - **Excision alone** is usually insufficient for keloids and can even be counterproductive, as the recurring wound often leads to a larger keloid. - While excision can be part of a treatment plan, it is typically combined with supplementary therapies like **steroid injections** or **radiation therapy** to prevent recurrence. *It contains growth factors.* - While keloids involve abnormal fibroblast activity and deposition of **extracellular matrix**, the statement that it "contains growth factors" is too vague and not a defining characteristic that differentiates it from a range of other tissues or conditions. - Many tissues and healing processes involve growth factors, so this statement alone does not provide a specific or most true characteristic of keloids. *None of the options.* - This option is incorrect because the statement that **keloids may extend beyond the original wound** is a hallmark characteristic of keloids and is definitively true.

Q: Acute Hemorrhagic Conjunctivitis is primarily caused by which type of Enterovirus?

Enterovirus type 70. ***Enterovirus type 70*** - **Enterovirus type 70** is the most common cause of **Acute Hemorrhagic Conjunctivitis (AHC)**, particularly in epidemic outbreaks. - AHC presents with rapid onset of **ocular pain**, **redness**, **swelling**, and **subconjunctival hemorrhages**. *Enterovirus type 68* - **Enterovirus D68 (EV-D68)** is primarily known for causing **respiratory illnesses**, ranging from mild to severe, and is associated with acute flaccid myelitis. - While it can cause respiratory symptoms, it is not a primary cause of **Acute Hemorrhagic Conjunctivitis**. *Enterovirus type 69* - **Enterovirus type 69** is a rare serotype and is not typically associated with specific human diseases or large-scale outbreaks. - Unlike EV70, it is not recognized as a significant cause of **conjunctivitis**. *Enterovirus type 71* - **Enterovirus A71 (EV-A71)** is a common cause of **hand, foot, and mouth disease (HFMD)**, especially in children, and can also lead to severe neurological complications. - While it causes various infections, it is not the primary cause of **hemorrhagic conjunctivitis**.

Q: Cutaneous larva migrans is caused by which organism?

Ancylostoma braziliense. ***Ancylostoma braziliense*** - This **hookworm** species commonly found in dogs and cats is the most frequent cause of **cutaneous larva migrans** in humans. - The larvae penetrate the skin but cannot complete their life cycle in humans, instead migrating aimlessly creating **serpiginous tracks**. *Strongyloides* - **_Strongyloides stercoralis_** causes **strongyloidiasis**, which presents with a rapidly advancing (up to 10 cm/hr) migratory rash known as **larva currens**, and not the slower cutaneous larva migrans. - It differs from cutaneous larva migrans in its ability to complete its life cycle in humans, leading to **autoinfection**. *Toxocara canis* - **_Toxocara canis_** is the causative agent of **visceral larva migrans** and **ocular larva migrans**, not cutaneous larva migrans. - In visceral larva migrans, larvae migrate through internal organs, causing symptoms like **hepatomegaly** and **eosinophilia**. *Necator americanus* - This is a human hookworm that can cause **iron deficiency anemia** due to chronic blood loss in the intestines. - While its larvae can penetrate the skin, causing a transient itchy rash known as **ground itch**, they do not cause the prolonged, migratory cutaneous larva migrans.

Q: What are the effects of Progesterone-only pills?

All of the options may occur. ***All of the options may occur*** - Progesterone-only pills (POPs) work through **multiple complementary mechanisms** that collectively provide effective contraception. - All three effects occur simultaneously and contribute to the overall contraceptive efficacy of POPs. - Understanding these mechanisms helps explain why POPs are effective despite lower hormone doses compared to combined oral contraceptives. **Mechanism 1: May suppress ovulation** - POPs can **partially suppress ovulation**, preventing the release of an egg. - Traditional POPs suppress ovulation in approximately 40-60% of cycles, while newer desogestrel-containing POPs achieve higher rates (97-99%). - This effect depends on the dose and type of progestin used in the formulation. **Mechanism 2: Thins the lining of the uterus** - Progesterone causes **endometrial atrophy**, making the uterine lining thin and unsuitable for embryo implantation. - This hostile uterine environment acts as a backup contraceptive mechanism if ovulation and fertilization occur. - Endometrial changes occur consistently with POP use. **Mechanism 3: Thickens cervical mucus** - This is the **primary and most consistent mechanism** of POPs. - Progesterone significantly **increases cervical mucus viscosity** and reduces its quantity within hours of administration. - The thickened mucus creates a physical barrier that prevents sperm penetration, motility, and viability.

Q: Extramammary Paget's disease of the vulva is most commonly associated with which other cancer?

Vulvar cancer. ***Vulvar cancer*** - **Extramammary Paget's disease (EMPD)** frequently presents in the vulvar region and is associated with an underlying **adenocarcinoma** in up to 30% of cases. - The disease involves intraepithelial adenocarcinoma cells that can spread locally and, in some instances, indicates a synchronous or metachronous **internal malignancy**, often of genitourinary or gastrointestinal origin, but primarily vulvar adenocarcinoma in this context. *Vaginal cancer* - While Paget's disease can occur in other anogenital areas, its association with **primary vaginal cancer** is much less common compared to vulvar involvement. - **Vaginal Paget's disease** is rare and usually represents secondary spread from a vulvar primary or an underlying bladder/urethral carcinoma. *Cervical cancer* - **Paget's disease** is not typically associated with **cervical cancer**. Cervical cancers are predominantly squamous cell carcinomas or adenocarcinomas arising from the transformation zone. - While cervical adenocarcinoma can present with similar cells to Paget's, it is a distinct entity and not a common association. *Uterine cancer* - **Uterine cancer**, primarily endometrial carcinoma, has no direct or common association with **Paget's disease**. - Paget's disease primarily affects the skin and can be associated with underlying gland cancers, but these are generally in proximity to the epidermal involvement rather than distant uterine sites.

Q: What is the physiological dose of hydrocortisone (mg/m2/day)?

10-12 mg/m²/day. ***10-12 mg/m²/day*** - This range represents the typical **physiological replacement dose** of hydrocortisone, mimicking the body's natural cortisol production. - This dose is used for patients with **adrenal insufficiency** to maintain normal metabolic functions without causing significant side effects. *8-10 mg/m²/day* - This dose is slightly on the lower side of the accepted physiological range and might not be sufficient for complete replacement in all individuals. - While close, it is not the most commonly cited optimal physiological dose for hydrocortisone replacement. *15-18 mg/m²/day* - This dose is typically considered above the physiological replacement level and may begin to cause **mild corticosteroid side effects** with prolonged use. - It might be used for short periods or in specific conditions, but not as a standard physiological replacement. *20-25 mg/m²/day* - This dose is well above the physiological range and would be considered a **pharmacological dose** often used for its anti-inflammatory or immunosuppressive effects. - Prolonged use at this dose would likely lead to significant **corticosteroid side effects** such as Cushingoid features, osteoporosis, and hyperglycemia.

Q: Which drug decreases the bone resorption in osteoporosis?

Risedronate. ***Risedronate*** - **Risedronate** is a **bisphosphonate**, a class of drugs that inhibits osteoclast activity, thereby decreasing **bone resorption**. - By reducing the rate at which bone is broken down, it helps to preserve **bone mineral density** in patients with osteoporosis. *Teriparatide* - **Teriparatide** is a **parathyroid hormone analog** that primarily works by stimulating **osteoblast activity** to promote new bone formation. - While it treats osteoporosis, its primary mechanism is **anabolic** (bone building), not directly decreasing bone resorption as its main effect. *Cortisone* - **Cortisone** is a **glucocorticoid** that can actually *worsen* osteoporosis by increasing **bone resorption** and decreasing **bone formation** with long-term use. - It is used to treat inflammatory conditions, not to decrease bone resorption for osteoporosis. *Cimetidine* - **Cimetidine** is an **H2-receptor antagonist** used to reduce stomach acid production, commonly for conditions like GERD or ulcers. - It has no known effect on **bone metabolism** or **osteoporosis**.

Q: Which of the following statements is true about the suture material shown in the image?

Degraded by enzymatic degradation. ***Degraded by enzymatic degradation*** - Catgut sutures are **natural absorbable sutures** made primarily from purified collagen. - Their absorption in the body occurs through **enzymatic degradation** and phagocytosis, which is a key characteristic distinguishing them from synthetic absorbable sutures that undergo hydrolysis. *Made of cat submucosa* - While historically referred to as "catgut," these sutures are not actually made from cat intestines. - They are typically derived from the **submucosa of sheep or goat intestines**. *Not degraded* - Catgut sutures are explicitly classified as **absorbable surgical sutures**, as stated on the packaging. - Absorbable sutures by definition are designed to be broken down and **resorbed by the body** over time. *Made of rabbit submucosa* - Catgut sutures are not typically made from rabbit submucosa. - The primary sources for natural absorbable sutures like catgut are the **intestines of sheep or goats**.

Question 1

What do chaperones assist in?

Accepted Answer

Protein Folding

Answer

Protein Cleavage

Answer

Protein Degradation

Answer

Protein Modification

Question 2

Which vitamin deficiency is associated with night blindness?

Accepted Answer

Vit. A

Answer

Biotin

Answer

Thiamine

Answer

Riboflavin

Question 3

Which of the following statements about keloids is MOST true?

Accepted Answer

Keloids may extend beyond the original wound.

Answer

Extended excision is often not the treatment of choice.

Answer

It contains growth factors.

Answer

None of the options.

Question 4

Acute Hemorrhagic Conjunctivitis is primarily caused by which type of Enterovirus?

Accepted Answer

Enterovirus type 70

Answer

Enterovirus type 68

Answer

Enterovirus type 69

Answer

Enterovirus type 71

Question 5

Cutaneous larva migrans is caused by which organism?

Accepted Answer

Ancylostoma braziliense

Answer

Strongyloides

Answer

Toxocara canis

Answer

Necator americanus

Question 6

What are the effects of Progesterone-only pills?

Accepted Answer

All of the options may occur

Answer

May suppress ovulation

Answer

Thins the lining of the uterus

Answer

Thickens cervical mucus

Question 7

Extramammary Paget's disease of the vulva is most commonly associated with which other cancer?

Accepted Answer

Vulvar cancer

Answer

Vaginal cancer

Answer

Cervical cancer

Answer

Uterine cancer

Question 8

What is the physiological dose of hydrocortisone (mg/m2/day)?

Accepted Answer

10-12 mg/m²/day

Answer

20-25 mg/m²/day

Answer

15-18 mg/m²/day

Answer

8-10 mg/m²/day

Question 9

Which drug decreases the bone resorption in osteoporosis?

Accepted Answer

Risedronate

Answer

Teriparatide

Answer

Cortisone

Answer

Cimetidine

Question 10

Which of the following statements is true about the suture material shown in the image?

Accepted Answer

Degraded by enzymatic degradation

Answer

Made of cat submucosa

Answer

Not degraded

Answer

Made of rabbit submucosa

NEET-PG 2018

Biochemistry

Dermatology

Microbiology

Obstetrics and Gynecology

Pharmacology

Surgery