NEET-PG 2015 - Pathology PYQs Practice Questions

Q: Gastric carcinoma is associated with all of the following EXCEPT:

Activation of RAS. ***Activation of RAS*** - **RAS mutations** are relatively uncommon in gastric carcinoma compared to other gastrointestinal malignancies. While KRAS mutations can occur in approximately 10-15% of gastric cancers (particularly intestinal type), they are **far less frequent** than in **pancreatic adenocarcinoma** (~90%) or **colorectal carcinoma** (~40%). - In the context of gastric carcinoma, RAS pathway alterations are **not considered a major oncogenic driver** compared to the other molecular changes listed, making this the **LEAST characteristically associated** alteration. *Inactivation of p53* - **Inactivation of the p53 tumor suppressor gene** is one of the most frequent molecular events in gastric carcinoma, occurring in approximately **50-60% of cases**. - Loss of p53 function leads to genomic instability, uncontrolled cell proliferation, and resistance to apoptosis, contributing significantly to **tumorigenesis** and **poor prognosis**. *Over expression of C-met* - **Overexpression of C-MET**, a receptor tyrosine kinase for hepatocyte growth factor (HGF), is commonly observed in gastric carcinoma (30-40% of cases) and is strongly linked to **tumor growth**, **invasion**, and **metastasis**. - C-MET amplification and overexpression promote cell proliferation, survival, migration, and angiogenesis, making it an important **therapeutic target** in advanced gastric cancer. *Over expression of C-erb* - **Overexpression of C-erbB-2 (HER2/neu)** is found in approximately **10-20% of gastric adenocarcinomas**, particularly the intestinal type. - HER2 amplification or overexpression is a significant **prognostic and predictive biomarker**, and is specifically targeted by **trastuzumab** (Herceptin) therapy in HER2-positive advanced gastric cancer, improving survival outcomes. [Practice more Pathology PYQs on OnCourse]

Q: During cell death, myelin figures are derived from which of the following?

Cell membrane (lipid bilayer). ***Cell membrane (lipid bilayer)*** - **Myelin figures** are whorled phospholipid masses formed during cell injury and death from the breakdown of **cellular membranes**, particularly the plasma membrane and **endoplasmic reticulum**. - These structures represent damaged membrane lipids (phospholipids) that undergo structural rearrangement into concentric lamellar (layered) configurations resembling myelin. - The term "cell membrane" encompasses both the plasma membrane and lipid-rich intracellular membranes, making this the most accurate answer among the options provided. - They are a characteristic morphologic feature of **irreversible cell injury** and can be seen with electron microscopy. *Cytoplasmic components* - While cytoplasmic proteins and organelles do degrade during cell death, they do not form the organized **phospholipid structures** characteristic of myelin figures. - Cytoplasmic breakdown produces different morphologic changes such as cytoplasmic eosinophilia and loss of ribosomes. *Mitochondrial structures* - Mitochondria have their own membranes that are damaged during cell death (leading to release of cytochrome c and other apoptotic factors). - However, mitochondrial membranes are not the primary source of **myelin figures**, which predominantly arise from ER and plasma membranes. *Nuclear membrane* - The nuclear envelope does fragment during cell death, contributing to nuclear changes like **karyopyknosis, karyorrhexis, and karyolysis**. - While technically a membrane structure, the nuclear envelope is not the primary source of myelin figures, which are mainly derived from the more abundant plasma and ER membranes. [Practice more Pathology PYQs on OnCourse]

Q: What is the characteristic feature of neuropraxia?

No structural damage to the nerve. ***No structural damage to the nerve*** - **Neuropraxia** is the mildest form of nerve injury, characterized by a **temporary block in nerve conduction** without structural damage to the axon or surrounding connective tissues. - This typically results in **temporary sensory and/or motor deficits** that fully resolve within weeks to months. *Damage to the endoneurium* - Damage to the **endoneurium** would indicate a more severe injury, such as **axonotmesis**, where the axon is damaged but the connective tissue sheaths are preserved. - This level of injury suggests that wallerian degeneration would occur distal to the lesion, leading to **slower and incomplete recovery**. *Damage to the epineurium* - Damage to the **epineurium**, along with the endoneurium and perineurium, signifies **neurotmesis**, the most severe nerve injury. - This involves a **complete transection of the nerve**, requiring surgical intervention for any chance of functional recovery. *Damage to the axon* - Damage to the **axon** itself, often alongside preserved connective tissues, is characteristic of **axonotmesis**. - While recovery is possible through axonal regeneration, it is **slower and less complete** than in neuropraxia. [Practice more Pathology PYQs on OnCourse]

Q: Hyaline degeneration is found in -

Alcoholic liver disease. ***Alcoholic liver disease*** - **Mallory bodies**, a form of hyaline degeneration, are characteristic histologic findings in hepatocytes in alcoholic liver disease. - They represent aggregates of **intermediate filaments** and other proteins, indicating severe hepatocellular damage. *Acute myocardial infarction* - Characterized by **coagulative necrosis** of cardiac myocytes due to ischemia, not hyaline degeneration. - Inflammation and subsequent repair with **fibrosis** are key features. *Alzheimer's disease* - Defined by the presence of **senile plaques** (amyloid-beta deposits) and **neurofibrillary tangles** (hyperphosphorylated tau protein). - These are specific protein aggregates, distinct from hyaline degeneration of cellular components. *Acute appendicitis* - Involves acute inflammation of the appendix, leading to **neutrophilic infiltration** and often **fibrinopurulent exudate**. - There is no characteristic hyaline degeneration associated with this inflammatory process. [Practice more Pathology PYQs on OnCourse]

Question 1

Gastric carcinoma is associated with all of the following EXCEPT:

Accepted Answer

Activation of RAS

Answer

Over expression of C-met

Answer

Inactivation of p53

Answer

Over expression of C-erb

Question 2

Which of the following statements about peripheral nerve injury is false?

Accepted Answer

Neuropraxia is irreversible

Answer

Wallerian degeneration starts in axonotmesis

Answer

Neurotmesis is the most severe form of injury

Answer

Epineurium is intact in axonotmesis

Question 3

During cell death, myelin figures are derived from which of the following?

Accepted Answer

Cell membrane (lipid bilayer)

Answer

Cytoplasmic components

Answer

Mitochondrial structures

Answer

Nuclear membrane

Question 4

What is the characteristic feature of neuropraxia?

Accepted Answer

No structural damage to the nerve

Answer

Damage to the endoneurium

Answer

Damage to the epineurium

Answer

Damage to the axon

Question 5

Hyaline degeneration is found in -

Accepted Answer

Alcoholic liver disease

Answer

Alzheimer's disease

Answer

Acute myocardial infarction

Answer

Acute appendicitis

Question 6

Which molecule is primarily responsible for nuclear fragmentation during apoptosis?

Accepted Answer

Caspases

Answer

Apaf - 1

Answer

Oxygen free radicals

Answer

Endonuclease G

Question 7

What is the first cellular response observed after a sharp nerve cut?

Accepted Answer

Chromatolysis

Answer

Polymorphic arrangement

Answer

Increased protein synthesis

Answer

Macrophage activation

Question 8

What is the definition of lipofuscin?

Accepted Answer

Wear and tear pigment

Answer

Fat deposits

Answer

Blood pigment

Answer

Form of calcification

Question 9

Which of the following is not an apoptotic gene?

Accepted Answer

n-myc (oncogene)

Answer

Mcl-1

Answer

Bax

Answer

P53

Question 10

What is the primary process involved in Wallerian degeneration?

Accepted Answer

Nerve degeneration

Answer

Muscle degeneration

Answer

Nerve regeneration

Answer

Muscle regeneration

NEET-PG 2015 — Pathology