FMGE 2018 Practice Questions

Q: Which part of thalamus is related to motor control?

Ventrolateral thalamus. ***Ventrolateral thalamus*** - The **ventrolateral (VL) nucleus** of the thalamus is a key relay station for **motor control**, receiving input from the **basal ganglia** and **cerebellum** and projecting to the motor cortex [1]. - It plays a crucial role in the planning, initiation, and coordination of **voluntary movements**. *Ventral posteromedial* - The **ventral posteromedial (VPM) nucleus** is involved in processing **somatosensory information** from the face and taste sensations. - It does not primarily contribute to motor control pathways. *Ventral posterolateral* - The **ventral posterolateral (VPL) nucleus** relays **somatosensory information** from the body (limbs and trunk) to the primary somatosensory cortex. - Its main function is sensory perception, not motor control. *Lateral geniculate nucleus* - The **lateral geniculate nucleus (LGN)** is exclusively involved in the **visual pathway**, receiving input from the retina and projecting to the primary visual cortex. - It has no direct role in motor control.

Q: Atherosclerosis is associated with:

Homocysteine. ***Homocysteine*** - Elevated plasma levels of **homocysteine**, known as hyperhomocysteinemia, are an independent **risk factor for atherosclerosis** and cardiovascular disease. - While the precise mechanism is complex, homocysteine is thought to promote endothelial damage, oxidative stress, and lipid peroxidation, contributing to **plaque formation**. *Histidine* - **Histidine** is an essential amino acid involved in various metabolic processes, including the synthesis of **histamine** and carnosine. - It is not directly associated with the pathogenesis or risk factors for atherosclerosis. *Lysine* - **Lysine** is an essential amino acid important for **protein synthesis** and many bodily functions. - There is no established direct link between lysine levels and the development or progression of atherosclerosis. *Leucine* - **Leucine** is a branched-chain amino acid (BCAA) crucial for **muscle protein synthesis** and energy metabolism. - While some studies hint at associations between BCAAs and metabolic health, leucine itself is not a known direct risk factor or etiologic agent for atherosclerosis.

Q: Young's operation is done for:

Atrophic rhinitis. ***Atrophic rhinitis*** - **Young's operation** is a surgical procedure specifically designed to treat **atrophic rhinitis**. - The goal of the surgery is to narrow the nasal passages by creating a **synechia** (adhesion) to reduce airflow and improve the humidification and temperature of inspired air. *Allergic rhinitis* - Allergic rhinitis is primarily managed with **medical therapy**, including antihistamines, nasal corticosteroids, and allergen avoidance. - Surgical intervention, if considered, typically involves procedures like turbinate reduction, not Young's operation, and is less common for this condition. *Vasomotor rhinitis* - Vasomotor rhinitis is a **non-allergic, non-infectious condition** characterized by fluctuating nasal congestion and rhinorrhea, often triggered by irritants or temperature changes. - Treatment usually involves **medical management** with anticholinergics or nasal corticosteroids, and sometimes turbinate reduction, but not Young's operation. *Antrochoanal polyp* - An antrochoanal polyp is a benign growth originating in the **maxillary sinus** and extending into the choana. - The primary treatment is **surgical removal**, typically via endoscopic sinus surgery, which is distinct from Young's operation.

Q: A 15 years old Male presented with history of fever since 2 days, unable to swallow the food with muffled voice. On examination it is noted right tonsil is shifted to midline. What is the diagnosis:

Quincy. ***Quincy (Peritonsillar abscess)*** - This patient's presentation with **fever**, **dysphagia**, **muffled voice** (hot potato voice), and **tonsil shifted to the midline** is classic for a **peritonsillar abscess (Quincy)**. - The affected tonsil is pushed **medially toward the midline** by the collection of pus between the tonsillar capsule and the superior constrictor muscle. - The uvula is typically deviated to the **contralateral side**, and patients often have **trismus** and difficulty opening the mouth. - This is the **most common deep neck space infection** and typically follows acute tonsillitis. *Parapharyngeal abscess* - A **parapharyngeal abscess** would present with **severe trismus**, **neck swelling**, **torticollis**, and **bulging of the lateral pharyngeal wall**. - While it can push the tonsil medially, it more characteristically causes **anterolateral displacement** of the entire pharyngeal wall rather than isolated tonsillar displacement. - Patients typically have more pronounced **systemic toxicity** and **neck involvement** than seen with peritonsillar abscess. *Acute tonsillitis* - **Acute tonsillitis** presents with **bilateral tonsillar enlargement**, exudates, and pharyngeal erythema. - It does not cause **displacement of the tonsil to the midline** or significant **muffled voice**. - While fever and dysphagia are present, the physical examination finding of tonsillar shift indicates a suppurative complication (abscess formation). *Acute retropharyngeal abscess* - An **acute retropharyngeal abscess** occurs in the retropharyngeal space behind the posterior pharyngeal wall. - It presents with **neck stiffness**, **stridor**, **drooling**, **bulging of the posterior pharyngeal wall**, and **reluctance to extend the neck**. - It would **not cause visible displacement of the tonsil to the midline** as the abscess is in a different anatomical space. - More common in **young children** (under 5 years) than adolescents.

Q: Which one of the following is a major component in activation of the complement alternative pathway?

C3. ***C3*** - **C3** is a central component in all complement pathways. In the alternative pathway, spontaneous hydrolysis of **C3** leads to C3(H2O), initiating the formation of the **C3 convertase**. - This **C3 convertase** (C3bBb) further cleaves more **C3** into C3a and C3b, amplifying the pathway and leading to downstream complement activation. *C2* - **C2** is a crucial component of the **classical** and **lectin pathways**, where it is cleaved by C1s or MASP-2, respectively, to form C2b and C2a. - **C2a** then combines with C4b to form the **C3 convertase** (C4b2a) of these pathways; it does not play a direct role in initiating the alternative pathway. *C4* - **C4** is primarily involved in the **classical** and **lectin pathways**, where it is cleaved by C1s or MASP-2 to form C4a and C4b. - **C4b** binds to pathogens or immune complexes and then associates with C2a to form the **C3 convertase** (C4b2a), which is not part of the alternative pathway initiation. *C1* - **C1** is the initiating complex of the **classical complement pathway** and is composed of C1q, C1r, and C1s. - It recognizes and binds to antibody-antigen complexes or pathogen surfaces, but it has no direct role in the **alternative pathway activation**.

Q: Sarcoidosis is associated with

Anterior uveitis. ***Anterior uveitis*** - **Anterior uveitis**, particularly chronic granulomatous anterior uveitis, is the most common ocular manifestation of **sarcoidosis**. - It results from **non-caseating granulomas** affecting the iris and ciliary body. - Sarcoidosis can also cause intermediate uveitis, posterior uveitis, and panuveitis, but anterior uveitis is most frequently seen. - Characteristic findings include mutton-fat keratic precipitates and iris nodules (Koeppe and Busacca nodules). *Keratitis* - **Keratitis** (inflammation of the cornea) is less commonly associated with sarcoidosis compared to uveitis. - While ocular sarcoidosis can rarely cause interstitial keratitis or band keratopathy, direct corneal inflammation is not a hallmark feature. *Cataract* - **Cataracts** are not directly caused by sarcoidosis itself, but can be a complication of chronic uveitis or prolonged corticosteroid treatment. - The disease process of sarcoidosis does not primarily involve cataract formation. *Ectopia lentis* - **Ectopia lentis** (lens dislocation) is a rare condition usually associated with genetic disorders like **Marfan syndrome** or homocystinuria. - It is not a recognized ocular manifestation of sarcoidosis.

Q: Campimetry is used to measure:

Field of Vision. ***Field of Vision*** - **Campimetry** is a diagnostic test specifically designed to map and assess a person's **field of vision**, identifying blind spots or areas of diminished sight. - This technique is crucial for detecting and monitoring conditions that affect the optic nerve or visual pathways, such as **glaucoma** or neurological disorders. *Squint* - A **squint**, also known as strabismus, refers to a misalignment of the eyes. - Its assessment primarily involves tests of **ocular motility** and alignment, such as the cover test, rather than perimetry. *Pattern of retina* - The **pattern of the retina** is evaluated through direct visualization using an **ophthalmoscope** or other retinal imaging techniques like fundus photography or optical coherence tomography (OCT). - These methods provide structural information about the retina, not its functional visual field. *Malignant melanoma* - **Malignant melanoma** (in the context of the eye) is a tumor that can affect various parts of the eye, including the choroid, iris, or conjunctiva. - Its diagnosis involves clinical examination, imaging studies (**ultrasound**, OCT, **fluorescein angiography**), and sometimes biopsy, not primarily visual field testing.

Q: Histamine is secreted by:

Enterochromaffin-like cell (ECL cell). ***Enterochromaffin-like cell (ECL cell)*** - **Enterochromaffin-like (ECL) cells** are located in the gastric mucosa and are the primary source of histamine in the stomach. - Histamine released by ECL cells stimulates **parietal cells** to secrete hydrochloric acid. - Note: ECL cells are distinct from enterochromaffin (EC) cells, which primarily secrete serotonin. *Chief cell* - **Chief cells** primarily secrete pepsinogen, the inactive precursor of the digestive enzyme pepsin. - They also produce gastric lipase, which aids in fat digestion. *Oxyntic cell* - The term **oxyntic (or parietal) cell** refers to the same cell type responsible for secreting hydrochloric acid and intrinsic factor. - They do not directly secrete histamine; instead, their acid secretion is stimulated by histamine. *Parietal cell* - **Parietal cells** are responsible for secreting hydrochloric acid and intrinsic factor, crucial for vitamin B12 absorption. - Their acid secretion is stimulated by acetylcholine, gastrin, and **histamine** (released from ECL cells).

Q: Delivery of stimulus above threshold intensity leads to a constant amplitude of AP and is known as:

All or none law. ***All or none law*** - The **all-or-none law** states that if a stimulus reaches or exceeds the **threshold intensity**, a neuron will fire an action potential of a constant, maximal amplitude. - If the stimulus is below the threshold, no action potential will fire, meaning there is no partial or submaximal action potential. *Electrotonic potential* - **Electrotonic potentials** are subthreshold, local changes in membrane potential that decay with distance and time. - They are **graded**, meaning their amplitude is proportional to the stimulus intensity, unlike the fixed amplitude of an action potential. *Absolute refractory period* - The **absolute refractory period** is the time during an action potential when the membrane is completely unresponsive to further stimulation, no matter how strong. - This period is due to the **inactivation of voltage-gated sodium channels**, preventing another action potential from being generated. *Relative refractory period* - The **relative refractory period** is the time following the absolute refractory period when a **larger-than-normal stimulus** is required to elicit another action potential. - This occurs because some potassium channels are still open, and the membrane is hyperpolarized, making it harder to reach the threshold.

Q: Ectopia lentis in a child is seen in which of the following diseases?

Homocystinuria. ***Homocystinuria*** - Ectopia lentis (lens dislocation) is a characteristic feature of **homocystinuria**, often presenting at a young age. - The dislocation in homocystinuria is typically **inferomedial (inferonasally)** due to weakened zonular fibers. - Homocystinuria is an **inborn error of methionine metabolism** with elevated homocysteine levels. *Marfan syndrome* - While **Marfan syndrome** is the most common cause of ectopia lentis, the lens typically dislocates **superiorly and temporally**. - Marfan syndrome is a connective tissue disorder but is not primarily a metabolic disorder like homocystinuria. - Both conditions can present with ectopia lentis, but the direction of dislocation and associated features differ. *Sarcoidosis* - Ocular manifestations of sarcoidosis usually include **uveitis**, **conjunctivitis**, and **retinal vasculitis**, but not typically ectopia lentis. - Sarcoidosis is a multisystem granulomatous disease and is rare in young children presenting with ectopia lentis. *Wilson disease* - **Kayser-Fleischer rings**, which are deposits of copper in the cornea, are pathognomonic for Wilson disease. - Ocular involvement in Wilson disease does not typically involve ectopia lentis. *Alkaptonuria* - This condition is characterized by the accumulation of **homogentisic acid**, leading to **ochronosis** (black pigmentation) in cartilaginous tissues and urine that turns black on standing. - Ocular manifestations can include scleral pigmentation, but ectopia lentis is not a feature of alkaptonuria.

Question 1

Which part of thalamus is related to motor control?

Accepted Answer

Ventrolateral thalamus

Answer

Ventral posteromedial

Answer

Ventral posterolateral

Answer

Lateral geniculate nucleus

Question 2

Atherosclerosis is associated with:

Accepted Answer

Homocysteine

Answer

Histidine

Answer

Lysine

Answer

Leucine

Question 3

Young's operation is done for:

Accepted Answer

Atrophic rhinitis

Answer

Allergic rhinitis

Answer

Vasomotor rhinitis

Answer

Antrochoanal polyp

Question 4

A 15 years old Male presented with history of fever since 2 days, unable to swallow the food with muffled voice. On examination it is noted right tonsil is shifted to midline. What is the diagnosis:

Accepted Answer

Quincy

Answer

Acute tonsillitis

Answer

Parapharyngeal abscess

Answer

Acute retropharyngeal abscess

Question 5

Which one of the following is a major component in activation of the complement alternative pathway?

Accepted Answer

C3

Answer

C2

Answer

C4

Answer

C1

Question 6

Sarcoidosis is associated with

Accepted Answer

Anterior uveitis

Answer

Keratitis

Answer

Cataract

Answer

Ectopia lentis

Question 7

Campimetry is used to measure:

Accepted Answer

Field of Vision

Answer

Squint

Answer

Pattern of retina

Answer

Malignant melanoma

Question 8

Histamine is secreted by:

Accepted Answer

Enterochromaffin-like cell (ECL cell)

Answer

Chief cell

Answer

Oxyntic cell

Answer

Parietal cell

Question 9

Delivery of stimulus above threshold intensity leads to a constant amplitude of AP and is known as:

Accepted Answer

All or none law

Answer

Electrotonic potential

Answer

Absolute refractory period

Answer

Relative refractory period

Question 10

Ectopia lentis in a child is seen in which of the following diseases?

Accepted Answer

Homocystinuria

Answer

Sarcoidosis

Answer

Wilson disease

Answer

Alkaptonuria

Answer

Marfan syndrome

FMGE 2018

Anatomy

Biochemistry

ENT

Microbiology

Ophthalmology

Physiology

Psychiatry