NEET-PG 2018 - Anatomy PYQs Practice Questions

Q: Which of the following is not seen in the anterior mediastinum?

Neurogenic tumor. ***Neurogenic tumor*** - **Neurogenic tumors** typically arise from nerve tissue and are most commonly found in the **posterior mediastinum**. - The posterior mediastinum is the primary location for these tumors due to the presence of the **sympathetic chain**, intercostal nerves, and vagus nerve. *Thyroid tumour* - **Ectopic thyroid tissue** can be found in the anterior mediastinum, and this tissue can give rise to thyroid tumors [1]. - While less common than in the neck, substernal or **ectopic thyroid goiters** and carcinomas can present in this compartment [1]. *Thymoma* - The **thymus gland** is located in the anterior mediastinum, making thymoma (a tumor of the thymus) a classic anterior mediastinal mass [1]. - Thymomas are often associated with **paraneoplastic syndromes** like myasthenia gravis. *Lymphoma* - **Lymphatic tissue**, including lymph nodes, is plentiful in the anterior mediastinum [1]. - **Hodgkin's and non-Hodgkin's lymphoma** frequently present as masses in the anterior mediastinum, often causing symptoms due to compression of surrounding structures [1]. [Practice more Anatomy PYQs on OnCourse]

Q: Which of the following statements about Sibson's fascia is correct?

Covers apical part of lung. ***Covers apical part of lung*** - **Sibson's fascia**, also known as the **suprapleural membrane**, is a dense fascial layer that covers and reinforces the **apex of the lung** and pleura. - It protects the lung apex and helps to support structures in the **root of the neck**. *Part of scalenus anterior muscle* - Sibson's fascia is a **separate fascial structure** extending from the first rib to the C7 transverse process, and is not a part of the scalenus anterior muscle. - The **scalenus anterior muscle** is one of the muscles of the neck, and while anatomically related by proximity to the fascia, it is not structurally part of it. *Vessel pass above the fascia* - Key neurovascular structures like the **subclavian artery** and the **brachial plexus** pass *below* Sibson's fascia, as the fascia protects the lung apex. - The fascia acts as a barrier, separating the lung apex from the more superficial structures of the neck. *Attached to the inner border of 2nd rib* - Sibson's fascia is primarily attached to the **inner border of the first rib** and the transverse process of the seventh cervical vertebra. - Its attachment to the first rib is crucial for its supportive role over the lung apex. [Practice more Anatomy PYQs on OnCourse]

Q: Which thickened nerve is shown in the image?

Lesser occipital nerve. ***Lesser occipital nerve*** - The nerve shown in the image is the **lesser occipital nerve**, which originates from the **ventral rami of C2 and C3**. - It ascends along the **posterior border of the sternocleidomastoid muscle** and supplies sensation to the skin of the lateral scalp posterior to the auricle. - Its **superficial course** and characteristic location make it identifiable in the surgical field shown. - The lesser occipital nerve can be thickened in cases of **nerve entrapment, neuroma formation, or chronic irritation**. *Third occipital nerve* - The third occipital nerve is a branch of the **dorsal ramus of C3** (medial branch) and is the smallest of the occipital nerves. - It innervates the skin of the **lower occipital region** and supplies the C2-C3 zygapophyseal joint. - It follows a deeper course compared to the nerve shown in the image. *Greater occipital nerve* - The greater occipital nerve arises from the **dorsal ramus of C2** and is the largest occipital nerve. - It pierces the **semispinalis capitis** and **trapezius** muscles, emerging medial to the occipital artery. - It provides sensory innervation to the **scalp up to the vertex** and is the most common nerve involved in **occipital neuralgia**. - Its course is more **medial** than the nerve shown in the image, typically running closer to the midline. *Greater auricular nerve* - This nerve arises from the **ventral rami of C2 and C3** at Erb's point and ascends on the surface of the sternocleidomastoid muscle. - It provides sensory innervation to the skin over the **parotid gland, mastoid process, and both surfaces of the auricle**. - Its course is more **anterior and inferior** compared to the occipital nerves, making it distinguishable from the nerve shown in the image. [Practice more Anatomy PYQs on OnCourse]

Q: Ureteric bud develops from:

Mesonephros. ***Mesonephros*** - The **ureteric bud** arises as an outgrowth of the **mesonephric duct** (Wolffian duct), which is the duct of the mesonephros. - The ureteric bud emerges from the **caudal portion of the mesonephric duct** near its entry into the cloaca around the 5th week of development. - It plays a crucial role in forming the **collecting system of the kidney**, including the ureter, renal pelvis, major and minor calyces, and collecting ducts. - **Note:** While technically the ureteric bud arises from the mesonephric duct (not the mesonephric tubules), "mesonephros" is accepted as the answer referring to the mesonephric duct system. *Metanephros* - The **metanephric mesoderm** (metanephric blastema) is induced by the ureteric bud to form the **definitive kidney**. - The metanephros forms the **nephrons** (from Bowman's capsule to distal convoluted tubule). - It does not give rise to the ureteric bud; rather, it interacts with it through **reciprocal induction**. *Pronephros* - The **pronephros** is the first, transient, and **non-functional** kidney structure in human embryonic development. - It appears in the **cervical region** around week 4 and completely **regresses** by week 5. - It does not contribute to the formation of the ureteric bud or the adult kidney. *Genital sinus* - The **urogenital sinus** is derived from the ventral part of the cloaca after division by the urorectal septum. - It gives rise to the **bladder**, parts of the urethra, and contributes to external genitalia. - It is not involved in the development of the ureteric bud or the kidney's collecting system. [Practice more Anatomy PYQs on OnCourse]

Q: What is the primary tensor of the vocal cords?

Cricothyroid. ***Cricothyroid*** - The **cricothyroid muscle** is the principal tensor of the vocal cords, responsible for stretching and thinning them. - It achieves this by tilting the **thyroid cartilage** forward relative to the **cricoid cartilage**, increasing the distance between the **thyroid** and **arytenoid cartilages**. *Lateral Cricoarytenoid* - This muscle primarily functions as an **adductor** of the vocal cords, bringing them together. - It rotates the **arytenoid cartilages** medially, closing the **rima glottidis**. *Thyroarytenoids* - The **thyroarytenoid muscles** are located within the vocal cords and primarily act to **shorten and relax** the vocal cords. - They also contribute to **adduction** and can internally tense the vocal folds, but their main role is *not* primary tension. *Posterior cricoarytenoids* - The **posterior cricoarytenoid muscles** are the *only* muscles responsible for **abducting** (opening) the vocal cords. - They rotate the **arytenoid cartilages** laterally, thus widening the **rima glottidis**. [Practice more Anatomy PYQs on OnCourse]

Question 1

Which of the following is not seen in the anterior mediastinum?

Accepted Answer

Neurogenic tumor

Answer

Thyroid tumor

Answer

Lymphoma

Answer

Thymoma

Question 2

Which of the following statements about Sibson's fascia is correct?

Accepted Answer

Covers apical part of lung

Answer

Part of scalenus anterior muscle

Answer

Vessel pass above the fascia

Answer

Attached to the inner border of 2nd rib

Question 3

Which thickened nerve is shown in the image?

Accepted Answer

Lesser occipital nerve

Answer

Third occipital nerve

Answer

Greater auricular nerve

Answer

Greater occipital nerve

Question 4

Ureteric bud develops from:

Accepted Answer

Mesonephros

Answer

Metanephros

Answer

Pronephros

Answer

Genital sinus

Question 5

What is the primary tensor of the vocal cords?

Accepted Answer

Cricothyroid

Answer

Lateral Cricoarytenoid

Answer

Thyroarytenoids

Answer

Posterior cricoarytenoids

Question 6

Which of the following is NOT part of the special visceral efferent column?

Accepted Answer

Accessory nerve

Answer

Nucleus ambiguus

Answer

Glossopharyngeal n

Answer

Vagus nerve

Question 7

When does the basiocciput fuse with the basisphenoid?

Accepted Answer

5-7 years

Answer

8-10 years

Answer

2-4 years

Answer

12-15 years

Question 8

What type of joint is formed by the costal cartilages of the 8th and 9th ribs?

Accepted Answer

Interchondral joint

Answer

Synovial joint

Answer

Costochondral joint

Answer

Costovertebral joint

Question 9

Acute tonsillitis affects which nerve:

Accepted Answer

Glossopharyngeal Nerve

Answer

Facial Nerve

Answer

Trigeminal nerve

Answer

Vagus Nerve

Question 10

Nerves of the Branchial arches are derived from:

Accepted Answer

Neuroectoderm

Answer

Mesoderm

Answer

Endoderm

Answer

Neural crest

NEET-PG 2018 — Anatomy