FMGE 2024 Practice Questions

Q: Anencephaly occurs due to the inability of the neural tube to close at which week of intrauterine life?

4th week. ***4th week***- The development of the **neural tube** occurs during the 4th week of intrauterine life, with the **anterior neuropore** normally closing around day 25 after conception. - Failure of this anterior closure, specifically at the cranial end during the 4th week, results in the severe congenital anomaly known as **anencephaly** [1].*3rd week*- The 3rd week is when **neurulation** (the folding of the neural plate) is initiated and the neural groove is formed, not when the final critical closure occurs.- The developing embryo is undergoing **gastrulation** during the 3rd week (formation of the three germ layers), preceding the completion of neural tube closure.*5th week*- By the 5th week, the neural tube is typically completely closed, and the process of **primary brain vesiculation** (forebrain, midbrain, hindbrain) is actively underway.- A closure defect leading to anencephaly would have necessarily occurred earlier, during the 4th week.*2nd week*- The 2nd week of development is characterized by the formation of the **bilaminar germ disc** (epiblast and hypoblast) and implantation.- **neurulation** (the process that forms the neural tube) does not begin until the start of the 3rd week, making the 2nd week too early for this specific closure defect.

Q: Which type of ion channel is affected by mutations in the CFTR gene?

Chloride. ***Chloride***- The **CFTR** (Cystic Fibrosis Transmembrane Conductance Regulator) gene encodes an **ATP-gated chloride channel** that controls the movement of chloride ions across epithelial cell membranes.- Mutations in the CFTR gene cause defective chloride secretion and increased sodium and water reabsorption, leading to the dehydrated, thick mucus characteristic of **Cystic Fibrosis (CF)**.*Sodium*- While the lack of functional CFTR leads to excessive **sodium reabsorption** via the epithelial sodium channel (ENaC) in airways, CFTR itself is a chloride channel, not a sodium channel.- ENaC hyperactivity is a *secondary* effect resulting from the failure of CFTR to inhibit ENaC activity appropriately.*Potassium*- The primary role of the CFTR protein is not the regulation of potassium ions; potassium channels are distinct proteins involved in maintaining resting membrane potential and cell volume.- CFTR activity and the resultant disease phenotype are directly linked to chloride imbalance, not potassium transport defects.*Calcium*- CFTR does not function as a calcium channel; calcium channels are separate entities crucial for many cellular processes, including neurotransmitter release and muscle contraction.- Although intracellular calcium levels can sometimes modulate CFTR activity through signaling pathways, the channel protein itself transports chloride.

Q: Which HLA is associated with Reiter syndrome?

HLA-B27. ***HLA-B27*** - **HLA-B27** is the major histocompatibility complex (MHC) class I allele strongly associated with **Reiter syndrome** (now termed **Reactive Arthritis**) a component of the **seronegative spondyloarthropathies** [1]. - Approximately 60-80% of patients with Reactive Arthritis who present with the classic triad (urethritis, conjunctivitis, arthritis) are positive for **HLA-B27** [1]. *HLA-DR3* - **HLA-DR3** is primarily associated with several autoimmune disorders, including **Celiac Disease**, **Graves' Disease**, and **Systemic Lupus Erythematosus** (SLE). - It is an MHC class II allele, distinguishing it from the MHC class I linkage observed in Reactive Arthritis. *HLA-DQ8* - **HLA-DQ8** (often with HLA-DQ2) is a key genetic risk factor for **Celiac Disease**, playing a role in presenting gliadin peptides to T cells. - This allele is also associated with **Type 1 Diabetes Mellitus** but lacks a significant established association with the pathogenesis of the spondyloarthropathies. *HLA-DR4* - **HLA-DR4** carries the strongest genetic risk for **Rheumatoid Arthritis** (RA), particularly in individuals prone to developing severe, erosive disease. - While associated with generalized autoimmunity, **HLA-DR4** is not the primary marker for the seronegative spondyloarthropathies like Reactive Arthritis [2].

Q: Conjunctival xerosis is caused by which vitamin deficiency?

Vitamin A. ***Vitamin A***- Vitamin A is crucial for the maintenance and differentiation of **epithelial cells**, including those of the conjunctiva.- Deficiency leads to **xerophthalmia**, starting with **night blindness** and progressing to **conjunctival xerosis** (dryness) and eventual **keratomalacia**.*Vitamin K*- Vitamin K is essential for the hepatic synthesis of **clotting factors** (II, VII, IX, X).- Deficiency results in a **coagulopathy** characterized by **excessive bleeding** and prolonged prothrombin time (PT).*Vitamin C*- Vitamin C (*ascorbic acid*) is vital for the hydroxylation of **proline and lysine** during **collagen synthesis**.- Deficiency causes **Scurvy**, symptomatically involving **fragile capillaries**, **gingival swelling and bleeding**, and impaired wound healing.*Vitamin D*- Vitamin D's primary role is regulating **calcium and phosphate metabolism** to maintain bone health.- Deficiency leads to **Rickets** in children and **Osteomalacia** in adults, primarily affecting the skeletal system.

Q: A child with diarrhea was eager to drink, and the skin pinch went back slowly. Which of the following categories is the child classified into as per IMNCI?

Yellow. ***Yellow***- This classification applies when the child shows two or more signs of **'Some Dehydration'** according to IMNCI guidelines, which include **eagerly drinking/thirst** and the **skin pinch going back slowly** (less than 2 seconds but noticeably delayed).- The management for the Yellow category involves treating dehydration using **Oral Rehydration Salts (ORS)** (Plan B).*Pink*- The **Pink (Severe Dehydration) category** requires at least two signs such as **lethargy/unconsciousness**, inability to drink/drinking poorly, or the **skin pinch going back very slowly** (≥ 2 seconds).- The child is **eager to drink**, which rules out the severe dehydration sign of being **unable to drink** or **drinking poorly**.*Green*- The **Green (No Dehydration) category** is applied when the child does not exhibit sufficient signs to classify them into the 'Some' or 'Severe' dehydration categories.- Since the child demonstrates two definite signs of dehydration (**thirst** and **slow skin pinch**), the 'No Dehydration' classification is incorrect.*None*- IMNCI provides specific and comprehensive categories (**Green, Yellow, Pink**) for classifying dehydration status based on clinical signs.- The combination of **eager drinking** and **slow skin pinch** definitively places the child in the **Yellow (Some Dehydration)** category.

Q: A patient was given an antipsychotic drug, haloperidol, and the patient developed acute dystonia. Which is the next best step?

Give Benztropine. ***Give Benztropine***- **Acute dystonia** is a severe extrapyramidal symptom (EPS) requiring rapid intervention, often treated intramuscularly or intravenously.- **Benztropine** (an anticholinergic agent) is the drug of choice for the immediate management of acute dystonia, working to restore the balance between dopamine and acetylcholine.*Change to clozapine*- While **clozapine** has a significantly lower risk of causing acute dystonia, it is not the initial treatment for an acute episode due to its slow titration requirements and side-effect profile.- Switching to clozapine is a long-term strategy for patients intolerant to other antipsychotics, not an acute rescue medication.*Give Fluphenazine*- **Fluphenazine** is a high-potency first-generation antipsychotic, similar to haloperidol, which also carries a high risk of EPS.- Administering another high-potency antipsychotic would perpetuate the excessive **dopaminergic blockade** responsible for the acute dystonia.*Increase dose of haloperidol*- **Acute dystonia** is a direct dose-related side effect of D2 receptor blockade by haloperidol in the nigrostriatal pathway.- Increasing the dose of **haloperidol** would worsen the underlying neurochemical imbalance, thereby intensifying the dystonic symptoms.

Q: A group of people are travelling to the mountains, and a girl starts complaining of mountain sickness. What is the drug of choice?

Acetazolamide. ***Acetazolamide*** - This drug is the agent of choice for prophylaxis and treatment of **Acute Mountain Sickness (AMS)** due to its ability to accelerate **acclimatization**. - It functions as a **carbonic anhydrase inhibitor**, inducing a mild metabolic acidosis that stimulates the respiratory center, thereby increasing ventilation and improving blood oxygen saturation. *Promethazine* - This is an **antihistamine** (H1 blocker) often used for its potent **antiemetic** (nausea) and sedative effects. - While it may relieve nausea symptoms associated with AMS, it does not address the underlying physiological disturbances or enhance **acclimatization**. *Dimenhydrinate* - This medication is also an **antihistamine** typically employed to treat and prevent **motion sickness** and vertigo. - It lacks the crucial physiological mechanism (carbonic anhydrase inhibition) required to improve breathing efficiency and accelerate the body's response to **hypoxia**. *Thiazide* - This category of drugs, such as hydrochlorothiazide, are **diuretics** primarily used for hypertension and edema. - They do not possess the necessary respiratory stimulation properties of **Acetazolamide** and are therefore ineffective in treating or preventing mountain sickness.

Q: Which of the following is an atypical antipsychotic with the least metabolic side effects?

Ziprasidone. ***Ziprasidone*** - Among the atypical (second-generation) antipsychotics, **Ziprasidone** has the lowest risk regarding adverse **metabolic side effects**, including **weight gain**, dyslipidemia, and insulin resistance. - Due to its minimal impact on metabolic parameters, it is a preferred choice for patients with pre-existing **cardiovascular risk factors** or obesity. *Haloperidol* - Haloperidol is a **first-generation (typical)** antipsychotic, which primarily risks **extrapyramidal symptoms (EPS)** and elevated prolactin, rather than being an atypical agent. - While its metabolic risk is generally lower than high-risk atypicals (e.g., Olanzapine), it is not the correct classification for answering a question focusing on *atypical* drugs. *Risperidone* - Risperidone is an atypical antipsychotic but carries a **moderate to high risk** of causing significant **weight gain** and **hyperprolactinemia**. - Its metabolic profile is considerably worse than that of Ziprasidone or Aripiprazole. *Quetiapine* - Quetiapine carries a substantial risk profile regarding metabolic adverse effects, specifically high rates of **sedation** and clinically significant **weight gain**. - It is frequently linked to the development of **dyslipidemia** and **Type 2 diabetes mellitus**.

Q: Which of the following oxygen-sensitive channels is present in peripheral chemoreceptors?

K+. ***K+***- **Oxygen-sensitive K+ channels**, specifically members of the **TASK-like potassium channels** family, are central to the response of **glomus cells** in the carotid body to **hypoxia**.- When oxygen levels fall, these channels are **inhibited**, reducing K+ efflux and causing the cell membrane to **depolarize**, initiating the signaling cascade.*Na+*- While **voltage-gated Na+ channels** are essential for action potential generation in the afferent nerve, they are not the primary channels that directly sense changes in **pO2** within the glomus cells.- The initial depolarizing signal stems from the inhibition of K+ channels, not the activation or inhibition of Na+ channels.*Ca++*- **Voltage-gated Ca++ channels** open in response to the **depolarization** caused by K+ channel inhibition upon hypoxia.- The resulting **calcium influx** is mandatory for the final step: triggering the release of **neurotransmitters** (e.g., dopamine, ATP) that signal the brainstem.*Cl-*- **Cl- channels** (Chloride channels) are present in glomus cells and help regulate cell volume and membrane potential, but they do not function as the mechanism's primary oxygen sensor.- The entire chemosensing process is primarily governed by the modulation of **cation** movement (K+ efflux and subsequent Ca++ influx) rather than chloride flux.

Q: Which among the following is the least radiosensitive cell?

Platelets. ***Platelets*** - Platelets are **anuclear cell fragments** derived from megakaryocytes, lacking a nucleus and DNA, which makes them highly resistant to the direct cytotoxic effects of radiation. - They are one of the **least radiosensitive** circulating components; platelet counts typically require very high radiation doses to fall significantly. *Monocytes* - Monocytes are generally considered **moderately radiosensitive**, more susceptible to radiation-induced death than mature neutrophils or platelets. - They exhibit susceptibility to **interphase death** upon irradiation, although less sensitive than lymphocytes. *Lymphocytes* - Lymphocytes are the **most radiosensitive** mature circulating blood cells, undergoing rapid apoptosis (programmed cell death) even at low radiation doses (sub-2 Gy). - Their high sensitivity relates to their dependence on DNA integrity for survival and their prompt initiation of the **apoptotic pathway** following damage. *Neutrophils* - Mature neutrophils are considered relatively radiosensitive, but significantly **less sensitive than lymphocytes** and moderately less sensitive than monocytes. - Their numbers drop less rapidly than lymphocytes primarily because of a large pre-formed **reserve pool** in the bone marrow, providing temporary protection.

Question 1

Anencephaly occurs due to the inability of the neural tube to close at which week of intrauterine life?

Accepted Answer

4th week

Answer

2nd week

Answer

3rd week

Answer

5th week

Question 2

Which type of ion channel is affected by mutations in the CFTR gene?

Accepted Answer

Chloride

Answer

Calcium

Answer

Potassium

Answer

Sodium

Question 3

Which HLA is associated with Reiter syndrome?

Accepted Answer

HLA-B27

Answer

HLA-DQ8

Answer

HLA-DR3

Answer

HLA-DR4

Question 4

Conjunctival xerosis is caused by which vitamin deficiency?

Accepted Answer

Vitamin A

Answer

Vitamin K

Answer

Vitamin C

Answer

Vitamin D

Question 5

A child with diarrhea was eager to drink, and the skin pinch went back slowly. Which of the following categories is the child classified into as per IMNCI?

Accepted Answer

Yellow

Answer

Green

Answer

None

Answer

Pink

Question 6

A patient was given an antipsychotic drug, haloperidol, and the patient developed acute dystonia. Which is the next best step?

Accepted Answer

Give Benztropine

Answer

Give Fluphenazine

Answer

Increase dose of haloperidol

Answer

Change to clozapine

Question 7

A group of people are travelling to the mountains, and a girl starts complaining of mountain sickness. What is the drug of choice?

Accepted Answer

Acetazolamide

Answer

Thiazide

Answer

Promethazine

Answer

Dimenhydrinate

Question 8

Which of the following is an atypical antipsychotic with the least metabolic side effects?

Accepted Answer

Ziprasidone

Answer

Risperidone

Answer

Haloperidol

Answer

Quetiapine

Question 9

Which of the following oxygen-sensitive channels is present in peripheral chemoreceptors?

Accepted Answer

K+

Answer

Ca++

Answer

Na+

Answer

Cl-

Question 10

Which among the following is the least radiosensitive cell?

Accepted Answer

Platelets

Answer

Lymphocytes

Answer

Neutrophils

Answer

Monocytes

FMGE 2024

Anatomy

Biochemistry

Internal Medicine

Ophthalmology

Pediatrics

Pharmacology

Physiology

Radiology