NEET-PG 2015 Practice Questions

Q: Intercalated disc is present in:

Cardiac muscle. ***Cardiac muscle*** - **Intercalated discs** are unique structures found only in cardiac muscle, forming specialized cell-cell junctions [1]. - These discs contain **gap junctions** for electrical coupling and **desmosomes** for strong adhesion, allowing the heart muscle to contract in a coordinated fashion. *Smooth muscle* - **Smooth muscle cells** are spindle-shaped and lack striations and organized sarcomeres. - They do not possess intercalated discs; instead, communication and coordination are often mediated by **gap junctions** scattered along the cell membranes [2]. *Skeletal muscle* - **Skeletal muscle cells** are long, multinucleated, and highly organized with prominent striations [3]. - They do not have intercalated discs as individual muscle fibers are innervated separately and generally do not directly communicate via specialized junctions for coordinated contraction. *All of the options* - As **intercalated discs** are characteristic features *only* of **cardiac muscle**, this option is incorrect. - Their presence in all three muscle types would contradict the specific cellular organization of smooth and skeletal muscle.

Q: What is the estimated blood glucose level in mg/dL for a patient with an HbA1c of 8% based on the conversion formula?

200. ***200*** - The estimated average glucose (eAG) can be calculated from HbA1c using the formula: **eAG (mg/dL) = 28.7 × HbA1c (%) – 46.7**. - For an HbA1c of 8%, the calculation is: **28.7 × 8 – 46.7 = 229.6 – 46.7 = 182.9 mg/dL**, which is closest to 200 mg/dL among the given options. *120* - An eAG of 120-125 mg/dL would correspond to an **HbA1c between 5.8% and 6.0%**, which is below the given 8%. - This value typically reflects **well-controlled or pre-diabetic** blood glucose levels. *160* - An eAG of 160 mg/dL would correspond to an **HbA1c of approximately 7.0-7.2%**, which is lower than the given 8%. - This level is often the target for HbA1c in many **diabetic management guidelines**, but not for 8%. *240* - An eAG of 240 mg/dL would correspond to an **HbA1c of approximately 9.9%**, which is significantly higher than the given 8%. - This indicates **poorly controlled diabetes** and a much higher average blood glucose level.

Q: Most important carbohydrate store for maintaining blood glucose homeostasis -

Hepatic glycogen. ***Hepatic glycogen*** - The liver contains **100-120g of glycogen**, which is the most crucial carbohydrate store for **maintaining blood glucose homeostasis**. - **Hepatic glycogen** can be mobilized and released as glucose into the bloodstream to supply all body tissues, especially during fasting. - Although muscle glycogen is quantitatively larger (~400-500g), it cannot contribute to blood glucose as muscle lacks glucose-6-phosphatase. - The liver's unique ability to release free glucose makes hepatic glycogen the **most metabolically important** carbohydrate store. *Blood glucose* - **Blood glucose** (~5g total in circulation) represents carbohydrates available for immediate energy, not a storage form. - This is far too small to be considered a major carbohydrate reserve. *Glycogen in adipose tissue* - **Adipose tissue** primarily stores **fat (triglycerides)**, with negligible glycogen content. - Adipose tissue plays virtually no role in carbohydrate storage. *None of the options* - This is incorrect because **hepatic glycogen** is indeed the most important carbohydrate store for glucose homeostasis.

Q: Length of the fetus is 40 cm. What would be the age of gestation?

8 months. ***8 months*** - At **8 months** of gestation (approximately **32 weeks**), the average crown-heel length of a fetus is about **40-43 cm**. - Foetal growth charts and developmental milestones indicate a close correlation between this length and the corresponding gestational age. *4 months* - At **4 months** of gestation (approximately **16 weeks**), the fetus is much smaller, typically around **12-15 cm** in crown-heel length. - Significant organ development is underway, but growth in length is not as rapid as in later trimesters. *6 months* - At **6 months** of gestation (approximately **24 weeks**), the fetus measures around **28-30 cm** in crown-heel length. - This stage is marked by significant weight gain and further development of organs, but it is still short of 40 cm. *7 months* - At **7 months** of gestation (approximately **28 weeks**), the fetus's crown-heel length is typically around **35-38 cm**. - While closer to 40 cm, it usually falls slightly short, with the average 40 cm length being more characteristic of 8 months.

Q: Which of the following statements best describes a key characteristic of fingerprint development?

Fingerprints are fully formed before birth.. ***Fingerprints are fully formed before birth.*** - Fingerprints begin to develop during the **fetal stage**, specifically between the 10th and 17th weeks of gestation. - Once formed, their unique ridge patterns remain **unchanged throughout life**, except for changes due to injury or disease. *DNA analysis is the most specific method of identification.* - While **DNA analysis** is a highly specific method of identification, the statement refers to its specificity generally, not as a characteristic of fingerprint development itself. - Fingerprints are a distinct form of identification based on unique **dermal ridge patterns**, independent of genetic material. *The most common type of fingerprint is loops.* - It is true that **loops** are indeed the most common type of fingerprint pattern, occurring in about 60-70% of the population. - However, this statement describes a characteristic of fingerprint patterns, not a key characteristic of their **development** or formation. *None of the options are true.* - This option is incorrect because the statement that **fingerprints are fully formed before birth** is a key characteristic of fingerprint development. - This option would only be correct if all other statements were false.

Q: Base of sphenoid fuses with occiput at the age of -

20 years. ***20 years*** - The **spheno-occipital synchondrosis** typically fuses by the age of **20 to 25 years**, marking the cessation of growth in the cranial base. - This fusion is an important indicator of skeletal maturity and is often used in **forensic anthropology** for age estimation. *30 years* - Fusion of the **spheno-occipital synchondrosis** beyond the early twenties is considered late and is not the typical age for this event. - By 30 years, most cranial sutures and synchondroses are already fused. *40 years* - At 40 years of age, the **spheno-occipital synchondrosis** would have been completely fused for many years, making this an incorrect age for the fusion process itself. - This age is well past the usual developmental timeframe for cranial base closure. *50 years* - Fusion at 50 years would be an **anomalous finding** as this synchondrosis is known to fuse much earlier in life. - By this age, the skull is fully mature, and fusion events of this nature have long since completed.

Q: What is the time interval between somatic and molecular death?

1 - 2 hrs. ***1 - 2 hrs*** - The interval between **somatic death** (cessation of heart and respiration) and **molecular death** (death of individual cells) is typically 1 to 2 hours. - This time allows for the depletion of cellular energy reserves and the onset of irreversible cellular damage after the body's major systems have ceased functioning. *5-10 min* - This short interval is generally associated with the **depletion of oxygen** supply to the brain, leading to irreversible neurological damage, but not complete molecular death of all body cells. - Brain cells are highly sensitive to hypoxia and begin to die within minutes, but other body cells have varying tolerances. *10-30 min* - While some highly sensitive cells (like neurons) may experience **irreversible damage** or death within this timeframe, it is not long enough for the generalized molecular death of all body cells. - Organs like the heart or skeletal muscles can retain viability for longer periods post-somatic death due to anaerobic metabolism. *30 -1hr* - This is closer to the true interval for widespread molecular death but often still underestimates the time it takes for less metabolically active cells to fully succumb. - Some cellular processes can continue for up to an hour, but complete **irreversible cellular breakdown** across all tissues usually takes longer.

Q: Which of the following drugs is commonly used as a rescue medication for acute asthma attacks?

Salbutamol. ***Salbutamol*** - **Salbutamol** (albuterol) is a **short-acting beta-2 agonist (SABA)** that rapidly relaxes bronchial smooth muscle. - Its quick onset of action makes it ideal for immediate relief of **bronchoconstriction** during an acute asthma attack. - It is the **most commonly used** and **first-line rescue medication** for acute asthma worldwide. *Terbutaline* - **Terbutaline** is also a **short-acting beta-2 agonist (SABA)** similar to salbutamol and can be used as a rescue medication. - While it has comparable bronchodilator effects, **salbutamol is more commonly used** as the preferred rescue inhaler in clinical practice. - Both are SABAs, but salbutamol has become the standard first-choice rescue medication globally. *Theophylline* - **Theophylline** is a **methylxanthine** that acts as a bronchodilator but has a **narrow therapeutic index** and slower onset of action. - It is used as a **maintenance therapy** for chronic asthma and not as a rescue drug for acute exacerbations. *Budesonide* - **Budesonide** is an **inhaled corticosteroid (ICS)** used as a **long-term controller medication** to reduce airway inflammation. - It has a slow onset of action and is *not* effective for immediate relief during an acute asthma attack.

Q: Acetaminophen [Paracetamol] induced liver toxicity is due to which metabolite?

NAPQI. ***NAPQI*** - **N-acetyl-p-benzoquinone imine (NAPQI)** is a highly reactive and toxic metabolite produced during acetaminophen metabolism, especially in overdose situations [1, 3]. - When glutathione stores are depleted due to excessive NAPQI formation, this metabolite covalently binds to hepatic macromolecules, causing **hepatocellular damage and necrosis** [1, 3].*N-acetylcysteine* - **N-acetylcysteine (NAC)** is the antidote for acetaminophen overdose, not the toxic metabolite itself [2, 3]. - NAC works by replenishing hepatic **glutathione stores**, which helps detoxify NAPQI and prevent liver injury [2, 3].*Co-Q* - **Coenzyme Q10 (CoQ10)** is an endogenous antioxidant and electron carrier in the mitochondrial respiratory chain. - It is not a metabolite of acetaminophen and plays no direct role in acetaminophen-induced liver toxicity.*Cytochrome 'C'* - **Cytochrome c** is a protein involved in the electron transport chain in mitochondria and plays a critical role in apoptosis. - While cellular damage from NAPQI can eventually lead to cytochrome c release and apoptosis, cytochrome c itself is not a metabolite of acetaminophen or the direct cause of toxicity.

Q: Which triptan is available in nasal spray form?

Sumatriptan. ***Sumatriptan*** - **Sumatriptan** is available in multiple formulations, including **oral, subcutaneous injection, and nasal spray**, making it versatile for migraine treatment [1], [2]. - The nasal spray formulation allows for **faster absorption** and onset of action, which can be beneficial for patients with nausea or vomiting during migraine attacks [1]. *Rizatriptan* - **Rizatriptan** is primarily available in **oral tablet** and **orally disintegrating tablet** (ODT) forms [2]. - It does not have a commonly available nasal spray formulation for migraine treatment [2]. *Naratriptan* - **Naratriptan** is available as an **oral tablet** and is known for its **longer half-life** and generally milder side effect profile compared to sumatriptan [2]. - It is not available in a nasal spray formulation [2]. *Frovatriptan* - **Frovatriptan** is available exclusively as an **oral tablet** and is notable for having the **longest half-life** among triptans, making it useful for preventing recurring migraines [2]. - There is no nasal spray formulation for frovatriptan [2].

Question 1

Intercalated disc is present in:

Accepted Answer

Cardiac muscle

Answer

Smooth muscle

Answer

Skeletal muscle

Answer

All of the options

Question 2

What is the estimated blood glucose level in mg/dL for a patient with an HbA1c of 8% based on the conversion formula?

Accepted Answer

200

Answer

120

Answer

160

Answer

240

Question 3

Most important carbohydrate store for maintaining blood glucose homeostasis -

Accepted Answer

Hepatic glycogen

Answer

Blood glucose

Answer

Glycogen in adipose tissue

Answer

None of the options

Question 4

Length of the fetus is 40 cm. What would be the age of gestation?

Accepted Answer

8 months

Answer

4 months

Answer

6 months

Answer

7 months

Question 5

Which of the following statements best describes a key characteristic of fingerprint development?

Accepted Answer

Fingerprints are fully formed before birth.

Answer

DNA analysis is the most specific method of identification.

Answer

The most common type of fingerprint is loops.

Answer

None of the options are true.

Question 6

Base of sphenoid fuses with occiput at the age of -

Accepted Answer

20 years

Answer

30 years

Answer

40 years

Answer

50 years

Question 7

What is the time interval between somatic and molecular death?

Accepted Answer

1 - 2 hrs

Answer

5-10 min

Answer

10-30 min

Answer

30 - 1 hr

Question 8

Which of the following drugs is commonly used as a rescue medication for acute asthma attacks?

Accepted Answer

Salbutamol

Answer

Theophylline

Answer

Terbutaline

Answer

Budesonide

Question 9

Acetaminophen [Paracetamol] induced liver toxicity is due to which metabolite?

Accepted Answer

NAPQI

Answer

Co-Q

Answer

Cytochrome 'C'

Answer

N-acetylcysteine

Question 10

Which triptan is available in nasal spray form?

Accepted Answer

Sumatriptan

Answer

Rizatriptan

Answer

Naratriptan

Answer

Frovatriptan

NEET-PG 2015

Anatomy

Biochemistry

Forensic Medicine

Pharmacology