NEET-PG 2013 Practice Questions

Q: T cells in lymph node are present in:

Paracortical area. ***Paracortical area*** - The **paracortical area** contains a high concentration of **T cells**, particularly activated T cells in response to antigenic stimulation [1]. - It plays a crucial role in **immune responses**, bridging the cortex and medulla of the lymph node [1]. *Mantle layer* - The **mantle layer** surrounds the follicles and primarily consists of **B cells**, not T cells. - It is involved in the initial immune response but does not contain a significant number of T lymphocytes. *Medullary cords* - **Medullary cords** mainly contain **plasma cells** and macrophages, with very few T cells present. - Their primary function is the secretion of antibodies rather than T cell activation or response. *Cortical follicles* - **Cortical follicles** are primarily sites for **B cell activation and proliferation**. - While they may have some T cells at their periphery, the majority of T cells are located in the paracortical area.

Q: What is the primary effect of moderate alcohol consumption on cholesterol levels?

High-Density Lipoprotein (HDL). ***High-Density Lipoprotein (HDL)*** - Moderate alcohol consumption is known to **increase HDL cholesterol** levels. - HDL cholesterol helps in the **reverse cholesterol transport**, removing excess cholesterol from tissues and transporting it back to the liver for excretion. *Total cholesterol* - The effect of moderate alcohol on **total cholesterol** is less consistent and may vary, as it is a sum of HDL, LDL, and 20% of VLDL. - While HDL increases, other components might remain unchanged or show minimal variation, thus not making it the primary and direct effect. *Low-Density Lipoprotein (LDL)* - Moderate alcohol consumption generally has **little to no significant effect** on **LDL cholesterol** levels. - Some studies suggest a slight decrease or no change, but it is not the primary lipid affected. *Very Low-Density Lipoprotein (VLDL)* - There is generally **no significant direct effect** of moderate alcohol consumption on **VLDL cholesterol** levels. - Excessive alcohol intake, however, can elevate triglycerides, which are the main component of VLDL particles.

Q: At what stage does the contraction of a family typically begin?

Leaving home of the first child. ***Leaving home of the first child*** - The **departure of the first child** from the home marks the beginning of the **contraction phase** of the family life cycle. - This stage signifies a decrease in the number of active family members residing in the home, initiating the process of family shrinkage. *Marriage* - Marriage is the **initial stage** of the family life cycle, where a new family unit is formed, typically referred to as the **establishment phase**. - This phase focuses on **role adjustment** and bonding, not the contraction of the family size. *Birth of the first child* - The birth of the first child marks the beginning of the **expansion stage** of the family life cycle. - This stage is characterized by an **increase in family size** and the establishment of parental roles. *Birth of the last child* - The birth of the last child typically represents the **end of the expansion phase** and the beginning of the **stable or child-rearing phase**. - While it caps the increase in family size, it doesn't initiate the contraction, as all children are still living at home.

Q: If a claw hand develops in a patient with Leprosy, what is the classification of the deformity?

Grade II. A **claw hand** deformity, characterized by hyperextension of the metacarpophalangeal joints and flexion of the interphalangeal joints, indicates a significant and **visible disability** but the affected part is still functional to a limited degree. In the context of leprosy, this observable and permanent deformity falls under **Grade II** on the WHO disability grading scale, signifying a clear and established disability. This grade indicates **no disability** or deformity related to leprosy. A patient with a claw hand has an obvious physical deformity and functional impairment, thus not fitting this classification. This grade refers to a **detectable impairment** but **no visible deformity**. A claw hand is a clearly visible deformity, making Grade I an inappropriate classification. While Grades are typically 0, I, and II in the WHO disability grading for leprosy, some classifications might refer to severe, non-functional deformities as higher grades. However, Grade II adequately captures **visible and significant deformities** like a claw hand, and a Grade III is not a standard or commonly used classification for a claw hand in leprosy in the WHO system.

Q: Which of the following is NOT a sign of somatic death?

Rigor mortis. ***Rigor mortis*** - **Rigor mortis** is a post-mortem change, occurring hours after death, characterized by muscle stiffening due to chemical changes after somatic death. - While it's a definitive sign of death, it is a secondary change occurring *after* the cessation of vital functions, not a primary sign of **somatic death** itself. *Cessation of respiration* - The complete and irreversible **cessation of respiration** (breathing) is a primary indicator of somatic death, as oxygen supply to tissues is halted. - This signifies the failure of the **respiratory system** to sustain life functions. *Cessation of heart* - The permanent **cessation of heart** function (cardiac arrest) is a fundamental sign of somatic death, leading to a lack of circulation and nutrient/oxygen delivery. - This marks the breakdown of the **circulatory system**, essential for maintaining life. *No response to external stimuli* - The absence of any **response to external stimuli**, including pain, light, and sound, indicates the complete loss of brain function and consciousness. - This signifies the irreversible failure of the **nervous system**, a key component of somatic death.

Q: What is the drug of choice for a classical angina attack?

GTN. ***GTN*** - **Glyceryl trinitrate (GTN)** is the drug of choice for immediate relief of a classical angina attack because it rapidly dilates coronary arteries and peripheral blood vessels, reducing **myocardial oxygen demand** and improving blood flow [2]. - Its **nitric oxide** mediated vasodilatory effects quickly alleviate chest pain by decreasing **preload** and afterload [2], [3]. *CCBs* - **Calcium channel blockers (CCBs)** are used for long-term prevention of angina by reducing myocardial oxygen demand, but they are not the first-line treatment for acute relief due to their slower onset of action [1]. - While they can dilate coronary arteries and reduce heart rate/contractility, their role is more in **prophylaxis** rather than acute symptom management [1]. *β-blocker* - **Beta-blockers** are primarily used for chronic management and prevention of angina by reducing heart rate, contractility, and blood pressure, thereby decreasing myocardial oxygen demand. - They are generally avoided for acute angina attacks as they do not provide rapid symptomatic relief and can potentially worsen symptoms in some acute ischemic conditions. *Prazocin* - **Prazosin** is an **alpha-1 adrenergic blocker** primarily used to treat hypertension and benign prostatic hyperplasia. - It causes vasodilation but is not indicated for the treatment of acute angina, as its mechanism of action and onset of effect are not suitable for rapid relief of myocardial ischemia.

Q: What is the mechanism of action of aminoglycoside antibiotics?

Inhibition of protein synthesis. ***Inhibition of protein synthesis*** - Aminoglycosides **bind irreversibly to the 30S ribosomal subunit** of bacteria, interfering with the initiation complex formation and causing misreading of mRNA. - This leads to the production of **non-functional proteins** and ultimately bacterial cell death, making them bactericidal. *Disruption of the cell membrane* - This mechanism is characteristic of **polymyxins** (e.g., colistin), which interact with bacterial cell membranes, increasing permeability and causing leakage of intracellular contents. - Aminoglycosides do not primarily target the cell membrane for their bactericidal action. *Inhibition of DNA replication* - This mechanism is associated with **fluoroquinolones**, which inhibit bacterial topoisomerase II (DNA gyrase) and topoisomerase IV. - Aminoglycosides do not interfere with DNA synthesis or replication. *Inhibition of bacterial cell wall synthesis* - This is the mechanism of action for **beta-lactam antibiotics** (e.g., penicillins, cephalosporins) and **glycopeptides** (e.g., vancomycin), which target peptidoglycan synthesis. - Aminoglycosides do not affect the bacterial cell wall but rather their intracellular protein machinery.

Q: Which of the following is a mineralocorticoid antagonist?

Spironolactone. ***Spironolactone*** - **Spironolactone** is a **potassium-sparing diuretic** that acts as a competitive antagonist of **aldosterone** at the mineralocorticoid receptors in the renal tubules [1], [2]. - Its primary use is in conditions like **heart failure**, **cirrhosis with ascites**, and **primary hyperaldosteronism** (Conn's syndrome) [2]. *Inamrinone* - **Inamrinone** is a **phosphodiesterase-3 inhibitor** (PDE3 inhibitor) and is classified as an **inotropic agent**. - It increases **intracellular cAMP** in cardiac cells, leading to increased **contractility** and **vasodilation**, and is used in severe heart failure. *Nicorandil* - **Nicorandil** is a **potassium channel opener** and a **nitrate-like drug** that causes both venous and arterial vasodilation. - It is primarily used as an **antianginal agent** due to its ability to reduce cardiac workload and improve coronary blood flow. *Ketorolac* - **Ketorolac** is a **nonsteroidal anti-inflammatory drug (NSAID)** that primarily inhibits **cyclooxygenase (COX) enzymes**. - It is used for **short-term management of acute moderate to severe pain** and has no direct activity on mineralocorticoid receptors.

Q: Which of the following is a metabolite of hydroxyzine?

Cetirizine. ***Cetirizine*** - **Cetirizine** is the principal active metabolite of **hydroxyzine**, formed through the oxidation of the primary alcohol group of hydroxyzine [2]. - Both hydroxyzine and cetirizine are **H1-receptor antagonists**, but cetirizine is a **second-generation antihistamine** known for being less sedating due to its limited ability to cross the blood-brain barrier [2]. *Fexofenadine* - **Fexofenadine** is an active metabolite of **terfenadine**, not hydroxyzine [2]. - **Fexofenadine** is a second-generation antihistamine used to treat allergies, known for its non-sedating properties [3]. *Terfenadine* - **Terfenadine** is a second-generation antihistamine that was withdrawn from the market due to its cardiotoxicity, particularly the risk of **QT prolongation** and **Torsades de Pointes**. - Its active metabolite is **fexofenadine**, which does not cause similar cardiac issues [2]. *Azelastine* - **Azelastine** is an antihistamine primarily available as a **nasal spray** for the treatment of allergic rhinitis and conjunctivitis [1], [3]. - It is not a metabolite of hydroxyzine but a distinct therapeutic compound.

Q: Which of the following is responsible for localization of sound ?

Superior olivary nucleus. ***Superior olivary nucleus*** - The **superior olivary nucleus** is the first site in the auditory pathway where binaural (two-ear) input is integrated, which is crucial for **sound localization**. - It processes **interaural time differences (ITDs)** and **interaural level differences (ILDs)** to determine the horizontal position of a sound source. *Cochlear nerve* - The **cochlear nerve** transmits auditory information from the cochlea to the brainstem but does not perform the initial processing for sound localization. - It carries impulses for both ears independently, which are then integrated at higher centers. *Cochlea* - The **cochlea** is responsible for converting sound vibrations into electrical signals (transduction), encoding properties like pitch and loudness, but not directly for sound localization. - It acts as a mechanical analyzer, separating sound into its frequency components. *Cochlear nuclei* - The **cochlear nuclei** receive input solely from the ipsilateral cochlear nerve and primarily process monaural (one-ear) auditory information. - While they are a crucial relay in the auditory pathway, they do not integrate binaural cues for sound localization.

Question 1

T cells in lymph node are present in:

Accepted Answer

Paracortical area

Answer

Mantle layer

Answer

Medullary cords

Answer

Cortical follicles

Question 2

What is the primary effect of moderate alcohol consumption on cholesterol levels?

Accepted Answer

High-Density Lipoprotein (HDL)

Answer

Total cholesterol

Answer

Low-Density Lipoprotein (LDL)

Answer

Very Low-Density Lipoprotein (VLDL)

Question 3

At what stage does the contraction of a family typically begin?

Accepted Answer

Leaving home of the first child

Answer

Marriage

Answer

Birth of the first child

Answer

Birth of the last child

Question 4

If a claw hand develops in a patient with Leprosy, what is the classification of the deformity?

Accepted Answer

Grade II

Answer

Grade 0

Answer

Grade I

Answer

Grade III

Question 5

Which of the following is NOT a sign of somatic death?

Accepted Answer

Rigor mortis

Answer

Cessation of heart

Answer

No response to external stimuli

Answer

Cessation of respiration

Question 6

What is the drug of choice for a classical angina attack?

Accepted Answer

GTN

Answer

CCBs

Answer

β-blocker

Answer

Prazosin

Question 7

What is the mechanism of action of aminoglycoside antibiotics?

Accepted Answer

Inhibition of protein synthesis

Answer

Inhibition of DNA replication

Answer

Disruption of the cell membrane

Answer

Inhibition of bacterial cell wall synthesis

Question 8

Which of the following is a mineralocorticoid antagonist?

Accepted Answer

Spironolactone

Answer

Inamrinone

Answer

Nicorandil

Answer

Ketorolac

Question 9

Which of the following is a metabolite of hydroxyzine?

Accepted Answer

Cetirizine

Answer

Fexofenadine

Answer

Terfenadine

Answer

Azelastine

Question 10

Which of the following is responsible for localization of sound ?

Accepted Answer

Superior olivary nucleus

Answer

Cochlear nerve

Answer

Cochlea

Answer

Cochlear nuclei

NEET-PG 2013

Anatomy

Biochemistry

Community Medicine

Forensic Medicine

Pharmacology

Physiology