NEET-PG 2018 Practice Questions

Q: Which of the following indicates the 'flipping effect'?

LDH1 > LDH2. ***LDH1 > LDH2*** - The "flipping effect" specifically refers to an **increase in LDH1 activity** such that it surpasses LDH2 activity. - This pattern is a classic indicator of **myocardial injury**, particularly a **myocardial infarction (heart attack)**. *LDH2 > LDH1* - This is the **normal pattern** of LDH isoenzyme distribution in healthy individuals. - In healthy serum, **LDH2 is typically higher than LDH1**. *LDH2 > LDH3* - While LDH2 is normally higher than LDH3, this comparison is **not characteristic** of the "flipping effect." - The "flipping effect" specifically involves the relationship between **LDH1 and LDH2**. *LDH2 > LDH4* - This relationship is generally true in both normal and abnormal conditions, as **LDH2 is typically abundant** in serum. - It does not represent the specific **diagnostic pattern** known as the "flipping effect."

Q: Most abundant form of pro-vitamin A is:-

Beta carotene. ***Beta carotene*** - **Beta-carotene** is the most widely distributed and abundant form of **provitamin A** in plants. - It yields two molecules of **retinal** upon enzymatic cleavage, which can then be converted to **retinol**. *Retinol* - **Retinol** is the active form of **vitamin A** and is not a pro-vitamin. - It is derived from pro-vitamin A carotenoids or ingested directly as preformed vitamin A. *Alpha-carotene* - **Alpha-carotene** is another form of **provitamin A**, but it is **less abundant** than beta-carotene. - It yields only one molecule of **retinal** because of its asymmetric structure. *Retinaldehyde* - **Retinaldehyde** (retinal) is an intermediate metabolite in the **vitamin A pathway**, converted from provitamin A or retinol. - It is not considered a pro-vitamin but rather a direct precursor to other active forms of vitamin A, such as **retinol** and **retinoic acid**.

Q: Active metabolite in the synthesis of fatty acids is:

Malonyl CoA. ***Malonyl CoA*** - **Malonyl CoA** is the immediate **two-carbon donor** in fatty acid synthesis, formed from acetyl CoA and bicarbonate. - It adds **two-carbon units** to the growing fatty acid chain during each cycle of synthesis, making it the primary active metabolic form in this process. *Stearate (an end product of fatty acid synthesis)* - **Stearate** is a **saturated fatty acid end product** (C18:0) of fatty acid synthesis, not an active metabolite that directly participates in the elongation process. - While it is a result of fatty acid synthesis, it does not serve as a building block for further elongation in the manner of malonyl CoA. *Acetyl CoA (a precursor in fatty acid synthesis)* - **Acetyl CoA** is the **initial precursor** for fatty acid synthesis, which is then carboxylated to form malonyl CoA. - It is not the *active* two-carbon donor during the elongation steps of fatty acid synthesis itself, but rather the substrate for malonyl CoA synthesis. *Palmitate (an end product of fatty acid synthesis)* - **Palmitate** is the **primary 16-carbon saturated fatty acid** and is the usual end product of *de novo* fatty acid synthesis in humans. - Like stearate, it is an end product and does not serve as an active metabolic intermediate for chain elongation during the synthesis process itself.

Q: The study unit in Ecological study is:

Population. ***Population*** - In an **ecological study**, the primary unit of observation and analysis is a **group or population**, rather than individuals. - Researchers examine disease rates and exposures across different populations or within the same population over time, looking for correlations. *Case* - A **case** refers to an individual with a specific disease or outcome, which is the unit of study in case-control studies. - Ecological studies do not focus on individual cases but rather on aggregate data for groups. *Patient* - A **patient** is an individual under medical care, typically the unit of study in clinical trials or case series. - Ecological studies analyze health patterns at a broader, population level, not at the individual patient level. *Community* - While a community can represent a population, in the context of ecological studies, **population** is the more precise and universally accepted term for the unit of analysis. - The term "community" might imply a smaller or more specific social grouping than the broader "population" often considered in ecological studies.

Q: Factor V mutation most commonly initially presents as:-

Deep Vein Thrombosis (DVT). ***Deep Vein Thrombosis (DVT)*** - Factor V Leiden mutation is a common inherited **thrombophilia**, significantly increasing the risk of **venous thromboembolism (VTE)**. - While VTE encompasses DVT and pulmonary embolism, **DVT is the most frequent initial presentation** because it is the primary thrombotic event leading to other complications [2]. *Thrombosis* - This is a general term for the formation of a **blood clot** that obstructs blood flow. - While Factor V Leiden causes thrombosis, **DVT is a specific and common type** of thrombosis that typically presents first [1]. *Disseminated Intravascular Coagulation (DIC)* - DIC is a complex, life-threatening condition characterized by widespread activation of coagulation leading to both **thrombosis and hemorrhage**. - It is typically triggered by severe underlying conditions like sepsis or trauma, and is **not a primary presentation of Factor V Leiden mutation**. *Pulmonary Embolism (PE)* - PE occurs when a **blood clot travels to the lungs**, often originating from a DVT. - While Factor V Leiden increases PE risk, **DVT is usually the antecedent event** and thus the more common initial clinical presentation [1].

Q: Which of the following is a pathognomonic feature of Alzheimer's disease?

Plaques and tangles. ***Plaques and tangles*** - The presence of **amyloid plaques** (extracellular deposits of beta-amyloid protein) and **neurofibrillary tangles** (intracellular aggregates of hyperphosphorylated tau protein) are the defining neuropathological hallmarks of Alzheimer's disease [1]. These are considered **pathognomonic** features upon post-mortem examination. - While other neurological conditions can have some tauopathy or amyloid deposition, the specific combination, distribution, and extensive nature of these two pathologies are unique to Alzheimer's [1]. [3] *Presence of Lewy bodies* - **Lewy bodies** are abnormal aggregates of alpha-synuclein protein that are characteristic of **Parkinson's disease** and **Lewy body dementia** [3]. - Their presence indicates a distinct neurodegenerative process, separate from Alzheimer's disease. *Presence of Pick bodies* - **Pick bodies** are cytoplasmic inclusions composed primarily of tau protein, but they are characteristic of **Pick's disease**, a type of frontotemporal dementia [2]. - Pick's disease has a different clinical presentation and neuropathological profile than Alzheimer's disease [2]. *Red neuronal degeneration (general feature)* - **Red neuronal degeneration** refers to the morphological changes seen in neurons undergoing acute irreversible ischemic injury, such as during a **stroke**. - It is a general feature of acute neuronal death and is not specific to, nor a pathognomonic feature of, Alzheimer's disease. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1292-1294. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1294-1295. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Manifestations Of Central And Peripheral Nervous System Disease, pp. 721-722.

Q: Which of the following is NOT included in the resuscitation of a neonate with HR < 60/min?

None of the above. ***None of the above*** - All listed interventions—**endotracheal tube intubation**, **chest compressions**, and **adrenaline administration**—are standard components of neonatal resuscitation when the heart rate remains below 60 beats/min despite initial steps. - This question asks which is *NOT* included, implying that all options are, in fact, appropriate interventions in this critical scenario. *Endotracheal tube intubation* - This is a critical step in **securing the airway** and ensuring effective positive pressure ventilation when other methods fail or prolonged mechanical ventilation is anticipated. - It's indicated if the heart rate remains below 60 bpm despite adequate bag-mask ventilation and chest compressions. *Chest compression* - **Chest compressions** are initiated when the heart rate is less than 60 bpm *after* 30 seconds of effective positive pressure ventilation. - They are used in conjunction with positive pressure ventilation to improve cardiac output and myocardial perfusion. *Adrenaline* - **Adrenaline** is administered if the heart rate remains below 60 bpm *despite* adequate ventilation and chest compressions. - It acts as a potent **vasopressor** and **cardiac stimulant**, increasing heart rate and contractility.

Q: The following is a feature of Korsakoff's psychosis:-

Confabulation. ***Confabulation*** - **Confabulation**, or the fabrication of vivid but false memories, is a classic symptom of Korsakoff's psychosis, often used to fill gaps in memory. - This symptom arises from significant **anterograde and retrograde amnesia**, particularly for recent events. *Hallucination* - While hallucinations can occur in various neurological and psychiatric conditions, they are **not a primary or defining feature** of Korsakoff's psychosis. - Korsakoff's primarily involves memory impairment, not perceptual disturbances. *Encephalopathy* - **Encephalopathy** (Wernicke's encephalopathy) is the acute precursor to Korsakoff's psychosis, but not a feature of Korsakoff's itself. - Wernicke's encephalopathy is characterized by **acute confusion, ataxia, and ophthalmoplegia**, often resolving or progressing to Korsakoff's if untreated. *Ophthalmoplegia* - **Ophthalmoplegia** (paralysis or weakness of eye muscles) is a key symptom of **Wernicke's encephalopathy**, the acute phase of thiamine deficiency. - While Wernicke's can progress to Korsakoff's, ophthalmoplegia is generally **not a persistent feature** of chronic Korsakoff's psychosis.

Q: Expression and consequent release of previously repressed emotion is called as:-

Abreaction. ***Abreaction*** - **Abreaction** is the process of reliving a past traumatic experience and expressing the emotions associated with it, which were previously repressed. - This emotional release is considered a **cathartic experience** and is often therapeutic, helping to alleviate psychological symptoms. *Regression* - **Regression** is a defense mechanism characterized by returning to an earlier stage of development or a more primitive mode of functioning in response to stress. - It does not specifically involve the release of **repressed emotions**, but rather a retreat to earlier behavioral patterns. *Dissociation* - **Dissociation** involves a disruption of the normal integration of consciousness, memory, identity, emotion, perception, and behavior. - While it can involve detachment from trauma, it is not primarily about the **expression and release** of previously repressed emotions. *All of the options* - This option is incorrect because while dissociation and regression are psychological phenomena, only **abreaction** specifically describes the expression and release of previously repressed emotions.

Question 1

Which of the following indicates the 'flipping effect'?

Accepted Answer

LDH1 > LDH2

Answer

LDH2 > LDH1

Answer

LDH2 > LDH3

Answer

LDH2 > LDH4

Question 2

Most abundant form of pro-vitamin A is:-

Accepted Answer

Beta carotene

Answer

Retinol

Answer

Alpha-carotene

Answer

Retinaldehyde

Question 3

Active metabolite in the synthesis of fatty acids is:

Accepted Answer

Malonyl CoA

Answer

Stearate

Answer

Acetyl CoA

Answer

Palmitate

Question 4

The study unit in Ecological study is:

Accepted Answer

Population

Answer

Case

Answer

Patient

Answer

Community

Question 5

Factor V mutation most commonly initially presents as:-

Accepted Answer

Deep Vein Thrombosis (DVT)

Answer

Thrombosis

Answer

Disseminated Intravascular Coagulation (DIC)

Answer

Pulmonary Embolism

Question 6

Absence of differentiation is known as:-

Accepted Answer

Anaplasia

Answer

Dysplasia

Answer

Metaplasia

Answer

Hyperplasia

Question 7

Which of the following is a pathognomonic feature of Alzheimer's disease?

Accepted Answer

Plaques and tangles

Answer

Presence of Lewy bodies

Answer

Presence of Pick bodies

Answer

Red neuronal degeneration

Question 8

Which of the following is NOT included in the resuscitation of a neonate with HR < 60/min?

Accepted Answer

None of the above

Answer

Endotracheal tube intubation

Answer

Chest compression

Answer

Adrenaline

Question 9

The following is a feature of Korsakoff's psychosis:-

Accepted Answer

Confabulation

Answer

Hallucination

Answer

Encephalopathy

Answer

Ophthalmoplegia

Question 10

Expression and consequent release of previously repressed emotion is called as:-

Accepted Answer

Abreaction

Answer

Regression

Answer

Dissociation

Answer

All of the options

NEET-PG 2018

Biochemistry

Community Medicine

Internal Medicine

Pathology

Pediatrics

Psychiatry