FMGE 2019 - Anatomy Practice Questions

Q: Trigone of bladder is derived from?

Distal part of Mesonephric duct. Distal part of Mesonephric duct - The **trigone of the bladder** develops from the **caudal (distal) ends of the mesonephric ducts**, which are absorbed into the posterior wall of the forming bladder. - The mesonephric duct origin contributes to the **smooth muscle** of the trigone, giving it distinct structural characteristics compared to the rest of the bladder wall. - The trigone appears as a smooth triangular area bounded by the two ureteric orifices and the internal urethral orifice [1]. *Ventral part of Urogenital sinus* - The **ventral part of the urogenital sinus** primarily forms the **fundus and body of the urinary bladder**, but not the trigone. - This region undergoes differentiation to form the majority of the bladder's wall and provides the epithelial lining for the entire bladder including the trigone. *Distal part of Paramesonephric duct* - The **paramesonephric ducts (Müllerian ducts)** are primarily involved in the development of the female reproductive tract, forming the **fallopian tubes, uterus, and upper vagina**. - They do not contribute to the formation of the urinary bladder or its trigone. *Ventral part of Mesonephric duct* - While the mesonephric ducts are crucial, it is specifically the **distal (caudal) ends** that are incorporated into the bladder to form the trigone, not merely the general ventral part. - The more proximal parts of the mesonephric ducts in males develop into structures like the **epididymis, v\as deferens, seminal vesicles, and ejaculatory ducts**.

Q: In the shown lateral view, the structure marked with arrowhead is?

Trachea. ***Trachea*** - This is a lateral view of the thorax, and the **trachea** is the most anterior conduit in the superior mediastinum, visible as an **air-filled structure** anterior to the esophagus. - The arrowhead points to a vertical air column in the anterior aspect, consistent with the expected anatomical location and appearance of the **trachea**. *Pulmonary artery* - The **pulmonary artery** lies anterior to the main bronchi and usually branches before this level, and it is a vascular structure, not an air-filled lumen. - It would appear as a soft tissue density, not a radiolucent (dark) air-filled structure on an X-ray. *Left atrium* - The **left atrium** is located posteriorly to the ascending aorta and pulmonary artery, and it is a cardiac chamber, not an air-filled tubular structure. - It is also a soft tissue density and would not be visible as a distinct air-filled lumen on a lateral chest X-ray in this position. *Esophagus* - The **esophagus** is located posterior to the trachea, running behind it in the mediastinum. - While it is a tubular structure, it is usually not air-filled unless there is swallowed air or a pathology (e.g., hiatus hernia), and it would be located *behind* the structure indicated by the arrowhead.

Q: Visual loss due to cerebral degeneration is related to which artery?

Posterior cerebral artery. ***Posterior cerebral artery*** - The **posterior cerebral artery** supplies the **occipital lobe**, which contains the **primary visual cortex** [1], [2]. - **Infarction** or **degeneration** in this territory can directly lead to **visual field defects** or **cortical blindness** [3]. *Anterior cerebral artery* - The **anterior cerebral artery** supplies the **frontal lobes** and medial aspects of the **parietal lobes**, which are not primarily involved in visual processing [4]. - Occlusion typically causes **contralateral leg weakness** and **sensory loss**, and **behavioral changes**. *Internal carotid artery* - The **internal carotid artery** bifurcates into the **anterior** and **middle cerebral arteries** but does not directly supply the primary visual cortex for central vision [4]. - While it can cause **amaurosis fugax** (transient monocular vision loss) due to retinal ischemia, it is not responsible for cortical visual degeneration. *Middle cerebral artery* - The **middle cerebral artery** supplies the majority of the **lateral surface of the cerebral hemispheres**, including portions of the **temporal** and **parietal lobes** [4]. - While it can cause **homonymous hemianopia** if it affects the **optic radiations** in the temporal or parietal lobes, it does not directly supply the primary visual cortex in the occipital lobe where cerebral degeneration causing visual loss is localized.

Q: Adam's apple in males is formed by the

Thyroid cartilage. ***Thyroid cartilage*** - The "Adam's apple" is anatomically known as the **laryngeal prominence**, which is formed by the anterior-most projection of the **thyroid cartilage**. - This prominence is typically more pronounced in males due to **hormonal influences** during puberty that lead to a larger larynx and vocal cords. *Hyoid bone* - The **hyoid bone** is a U-shaped bone located superior to the larynx that supports the tongue, but it does not form the "Adam's apple." - It is unique because it is the only bone in the human body not articulating with any other bone. *Epiglottis cartilage* - The **epiglottis** is a leaf-shaped elastic cartilage that covers the entrance to the larynx during swallowing to prevent food and liquid from entering the trachea. - It is positioned posterior to the thyroid cartilage and is not externally visible as the "Adam's apple." *Cricoid cartilage* - The **cricoid cartilage** is a complete ring of hyaline cartilage located inferior to the thyroid cartilage, forming the base of the larynx. - While it's a part of the larynx, it does not form the anterior projection known as the "Adam's apple."

Q: Avascular necrosis of the femoral head most commonly occurs due to disruption of which of the following arteries?

Medial circumflex femoral artery. ***Medial circumflex femoral artery*** - The **medial circumflex femoral artery** is the primary blood supply to the **femoral head** and **neck**, particularly through its retinacular branches. - Interruption of this blood flow, often due to trauma or other conditions, is the most common cause of **avascular necrosis** of the femoral head. *Lateral circumflex femoral artery* - The **lateral circumflex femoral artery** primarily supplies the **vastus lateralis muscle** and parts of the greater trochanter. - It contributes minimally and indirectly to the blood supply of the femoral head. *Obturator artery* - The **obturator artery** primarily supplies structures in the medial compartment of the thigh and makes a small contribution to the femoral head via the **artery of the ligamentum teres**, which is generally insufficient to prevent avascular necrosis alone. - This artery is most significant in children, but by adulthood, its contribution to femoral head vascularity is minor. *Profunda femoris artery* - The **profunda femoris artery** (deep femoral artery) is the largest branch of the femoral artery and gives rise to the circumflex femoral arteries. - Its direct contribution to the femoral head blood supply is generally through its branches (like the circumflex arteries), rather than directly.

Question 1

Trigone of bladder is derived from?

Accepted Answer

Distal part of Mesonephric duct

Answer

Ventral part of Urogenital sinus

Answer

Distal part of Paramesonephric duct

Answer

Ventral part of Mesonephric duct

Question 2

In the shown lateral view, the structure marked with arrowhead is?

Accepted Answer

Trachea

Answer

Pulmonary artery

Answer

Left atrium

Answer

Esophagus

Question 3

Visual loss due to cerebral degeneration is related to which artery?

Accepted Answer

Posterior cerebral artery

Answer

Anterior cerebral artery

Answer

Internal carotid artery

Answer

Middle cerebral artery

Question 4

Adam's apple in males is formed by the

Accepted Answer

Thyroid cartilage

Answer

Hyoid bone

Answer

Epiglottis cartilage

Answer

Cricoid cartilage

Question 5

Avascular necrosis of the femoral head most commonly occurs due to disruption of which of the following arteries?

Accepted Answer

Medial circumflex femoral artery

Answer

Lateral circumflex femoral artery

Answer

Obturator artery

Answer

Profunda femoris artery

FMGE 2019 — Anatomy