NEET-PG 2015 - Anatomy Practice Questions

Q: Fossa ovalis is a remnant of -

Septum primum. ***Septum primum*** - The **fossa ovalis** is a depression in the right atrium that represents the sealed-off foramen ovale [2]. - It is formed from the **septum primum**, which becomes the floor of the fossa ovalis. *Septum secundum* - The **septum secundum** forms the limbus or rim of the fossa ovalis, not the fossa itself. - This structure develops later than the septum primum and partially covers the foramen ovale during fetal development [2]. *Septum spurium* - The **septum spurium** is an embryonic ridge in the right atrium that typically regresses during development and does not contribute to the fossa ovalis. - It is a transient structure formed by the confluence of the right and left venous valves. *AV cushion* - The **atrioventricular (AV) cushions** contribute to the formation of the AV valves and the atrial and ventricular septa, but not directly to the fossa ovalis [1]. - They are crucial for separating the atria from the ventricles and forming the mitral and tricuspid valves.

Q: Which of the following is not formed by the external oblique muscle?

Conjoint tendon. ***Conjoint tendon*** - The **conjoint tendon** is formed by the conjoined aponeuroses of the **internal oblique** and **transversus abdominis muscles**, not the external oblique [1]. - It provides posterior wall reinforcement to the inguinal canal. - This is the structure that is definitively **NOT formed by the external oblique muscle**. *Lacunar ligament* - The **lacunar ligament** (Gimbernat's ligament) is a triangular fascial band formed by the medial reflection of the **inguinal ligament**. - It is derived from the **external oblique aponeurosis** and forms the medial boundary of the femoral ring. *Pectineal ligament* - The **pectineal ligament** (Cooper's ligament) is a thickening of the periosteum along the pecten pubis (pectineal line) [3]. - While it is continuous with the lacunar ligament, it is not directly formed by the external oblique muscle itself, but rather represents a separate periosteal structure. - For the purposes of this question, the conjoint tendon is the most appropriate answer as it has no contribution from the external oblique. *Inguinal ligament* - The **inguinal ligament** (Poupart's ligament) is formed by the inferomedial border of the **external oblique aponeurosis**, folding back on itself [2]. - It spans between the **anterior superior iliac spine** and the **pubic tubercle**.

Q: Lining epithelium of vagina is

Squamous epithelium. Squamous epithelium * The vagina is lined by stratified squamous non-keratinized epithelium [1], providing a protective barrier against friction and pathogens. * This type of epithelium is well-suited for areas subject to significant mechanical stress, such as during intercourse and childbirth. Columnar epithelium * Columnar epithelium [2] is typically found in areas specialized for secretion and absorption, such as the gastrointestinal tract and glandular linings. * It would not offer the necessary protective qualities for the vaginal environment. Transitional epithelium * Transitional epithelium is a specialized stratified epithelium found in the urinary tract, capable of stretching and distending. * It is not found in the vagina, which requires a more robust, friction-resistant lining. Secretory epithelium * While the cervix has secretory glands, the lining of the vagina itself is not primarily secretory. * The primary role of the vaginal lining is protection, not secretion, and its cells do not typically produce a large amount of substances.

Q: Teres minor is supplied by

Axillary nerve. ***Axillary nerve*** - The **axillary nerve** (C5-C6) innervates both the **teres minor** and the **deltoid muscle**. - It arises from the posterior cord of the brachial plexus and traverses the quadrangular space. *Suprascapular nerve* - The **suprascapular nerve** (C5-C6) primarily supplies the **supraspinatus** and **infraspinatus** muscles. - It plays a crucial role in shoulder abduction and external rotation, but not directly in teres minor function. *Lower subscapular nerve* - The **lower subscapular nerve** (C5-C6) innervates the **subscapularis muscle** and **teres major**. - Teres major and teres minor are anatomically adjacent but have different innervations and functions. *Thoracodorsal nerve* - The **thoracodorsal nerve** (C6-C8) innervates the **latissimus dorsi muscle** [1]. - This nerve is distinct from those supplying the rotator cuff muscles, including teres minor.

Q: Which of the following structures does NOT pass through the deep inguinal ring?

Ilioinguinal nerve. The ilioinguinal nerve typically passes through the superficial inguinal ring but does not travel through the deep inguinal ring [1]. It lies in the inguinal canal, superficial to the spermatic cord in males and the round ligament in females [1]. The spermatic cord in males enters the inguinal canal through the deep inguinal ring [2]. It contains structures like the vas deferens, testicular artery, pampiniform plexus, and nerves. The internal spermatic fascia is a covering of the spermatic cord that originates from the transversalis fascia at the deep inguinal ring [2]. In females, the round ligament of the uterus is the homologous structure to the spermatic cord in males, and it passes through the deep inguinal ring to enter the inguinal canal. It helps maintain the anteversion of the uterus.

Q: Which of the following statements about the lumbrical muscles is correct?

Flex MCP joints and extend IP joints. Flex MCP joints and extend IP joints - The lumbrical muscles are unique in their attachment, originating from tendons and inserting into the extensor hood, allowing them to perform simultaneous metacarpophalangeal (MCP) joint flexion and interphalangeal (IP) joint extension [1]. - This specific action is crucial for fine motor movements of the fingers, particularly in precision grip. All lumbricals are supplied by the median nerve - This statement is incorrect as only the first and second lumbricals (of the index and middle fingers) are typically supplied by the median nerve. - The third and fourth lumbricals are innervated by the ulnar nerve. All lumbricals are supplied by the ulnar nerve - This statement is incorrect because the first and second lumbricals receive innervation from the median nerve. - Only the third and fourth lumbricals are consistently supplied by the deep branch of the ulnar nerve. Origin from the tendons of flexor digitorum superficialis - This statement is incorrect. The lumbricals originate from the tendons of the flexor digitorum profundus, not the superficialis [1]. - They are unique in that they are the only muscles in the human body that originate from a tendon and insert into a tendon (extensor expansion) [1].

Q: The nerve which has the longest intracranial course is:

Trochlear nerve (Fourth cranial nerve). The nerve which has the longest intracranial course is: ***Trochlear nerve (Fourth cranial nerve)*** - This nerve has the **longest intracranial course** of all the cranial nerves, emerging from the dorsal aspect of the midbrain. - Its long path makes it particularly susceptible to **injury** from head trauma or increased intracranial pressure. *Oculomotor nerve (Third cranial nerve)* - While significant in length, the **oculomotor nerve** does not have the longest intracranial course; it emerges from the ventral midbrain. [1] - It controls most of the **extraocular muscles**, but its intracranial path is shorter than that of the trochlear nerve. *Abducens nerve (Sixth cranial nerve)* - The **abducens nerve** has a relatively long course within the pons and across the clivus but is not the longest. - It is often impacted in conditions causing **elevated intracranial pressure** or skull base fractures due to its path. *Trigeminal nerve (Fifth cranial nerve)* - The **trigeminal nerve** has a large sensory ganglion and extensive peripheral branches but its intracranial course is comparatively short, emerging from the pons. - It is primarily responsible for **facial sensation** and mastication.

Q: Uvula vesicae seen in bladder is formed from the following structure?

Median lobe of the prostate. ***Median lobe of the prostate*** - The **uvula vesicae** is a slight median elevation on the internal surface of the **bladder base**, immediately behind the **internal urethral orifice**. - This elevation is formed by the underlying **median (middle) lobe of the prostate** projecting upward beneath the bladder mucosa. - In **benign prostatic hyperplasia (BPH)**, enlargement of the median lobe accentuates this prominence and can cause significant urinary obstruction. *Lateral lobe of the prostate* - Enlargement of the **lateral lobes** causes lateral compression of the prostatic urethra, not a median elevation at the bladder neck. - While they are the most common site of **BPH**, they do not form the uvula vesicae. *Anterior lobe of the prostate* - The **anterior lobe** (or anterior fibromuscular stroma) is located in front of the urethra and is non-glandular. - It does not contribute to the formation of the uvula vesicae or cause significant urinary symptoms. *Posterior lobe of the prostate* - The **posterior lobe** is located behind the urethra and is the most common site for **prostate cancer**. - It does not project into the bladder base and therefore does not form the uvula vesicae.

Q: Largest cranial nerve is:

Trigeminal. ***Trigeminal*** - The **trigeminal nerve (CN V)** is the largest cranial nerve, both in terms of its overall diameter and the number of fibers it contains. - It has three major divisions: **ophthalmic, maxillary, and mandibular**, providing extensive sensory innervation to the face and motor innervation to the muscles of mastication. *Trochlear* - The **trochlear nerve (CN IV)** is the smallest cranial nerve in terms of diameter and number of axons. - It primarily innervates a single muscle, the **superior oblique muscle** of the eye. *Oculomotor* - The **oculomotor nerve (CN III)** is responsible for innervating several extrinsic eye muscles and plays a role in pupil constriction. - While significant, it is not the largest cranial nerve. *Vagus* - The **vagus nerve (CN X)** has the longest anatomical course among all cranial nerves, extending into the abdomen, but it is not the largest in terms of overall size or fiber count. - It carries extensive **parasympathetic fibers** and has broad effects on visceral organs.

Q: What is the uppermost structure in left lung hilum?

Pulmonary artery. ***Pulmonary artery*** - In the **left lung hilum**, the **pulmonary artery** typically lies superior to the bronchus. - This anatomical position helps differentiate it from the relations in the right lung hilum, where the pulmonary artery is anterior to the bronchus. *Pulmonary vein* - The **pulmonary veins** are usually located anterior and inferior to the bronchus in both lung hila. - They tend to be the most anterior and inferior structures carrying oxygenated blood from the lungs. *Bronchial artery* - **Bronchial arteries** are smaller vessels that typically run on the posterior surface of the bronchi. - They are not considered the uppermost main structure in the hilum. *Left mainstem bronchus* - The **left mainstem bronchus** is usually found inferior to the pulmonary artery and posterior to the pulmonary veins in the left hilum. - It is a prominent structure but not the most superior.

Question 1

Fossa ovalis is a remnant of -

Accepted Answer

Septum primum

Answer

Septum secundum

Answer

Septum spurium

Answer

AV cushion

Question 2

Which of the following is not formed by the external oblique muscle?

Accepted Answer

Conjoint tendon

Answer

Inguinal ligament

Answer

Lacunar ligament

Answer

Pectineal ligament

Question 3

Lining epithelium of vagina is

Accepted Answer

Squamous epithelium

Answer

Columnar epithelium

Answer

Transitional epithelium

Answer

Secretory epithelium

Question 4

Teres minor is supplied by

Accepted Answer

Axillary nerve

Answer

Suprascapular nerve

Answer

Lower subscapular nerve

Answer

Thoracodorsal nerve

Question 5

Which of the following structures does NOT pass through the deep inguinal ring?

Accepted Answer

Ilioinguinal nerve

Answer

Spermatic cord

Answer

Internal spermatic fascia

Answer

Round ligament

Question 6

Which of the following statements about the lumbrical muscles is correct?

Accepted Answer

Flex MCP joints and extend IP joints

Answer

All lumbricals are supplied by the median nerve

Answer

Origin from the tendons of flexor digitorum superficialis

Answer

All lumbricals are supplied by the ulnar nerve

Question 7

The nerve which has the longest intracranial course is:

Accepted Answer

Trochlear nerve (Fourth cranial nerve)

Answer

Oculomotor nerve (Third cranial nerve)

Answer

Abducens nerve (Sixth cranial nerve)

Answer

Trigeminal nerve (Fifth cranial nerve)

Question 8

Uvula vesicae seen in bladder is formed from the following structure?

Accepted Answer

Median lobe of the prostate

Answer

Lateral lobe of the prostate

Answer

Anterior lobe of the prostate

Answer

Posterior lobe of the prostate

Question 9

Largest cranial nerve is:

Accepted Answer

Trigeminal

Answer

Trochlear

Answer

Oculomotor

Answer

Vagus

Question 10

What is the uppermost structure in left lung hilum?

Accepted Answer

Pulmonary artery

Answer

Pulmonary vein

Answer

Bronchial artery

Answer

Left mainstem bronchus

NEET-PG 2015 — Anatomy