NEET-PG 2012 - Anatomy Practice Questions

Q: Lymphatic drainage of cervix is to

Iliac lymph nodes. ***Iliac lymph nodes*** - The primary lymphatic drainage of the cervix is to the **internal**, **external**, and **common iliac lymph nodes**. - This pathway is crucial for understanding the spread of **cervical cancer**. *Para-aortic lymph nodes* - While sometimes involved in advanced cases, the **para-aortic nodes** are typically considered a secondary drainage site, usually after the iliac nodes are affected. - They are the primary drainage for organs like the **ovaries** and **testes**. *Deep inguinal lymph nodes* - These nodes primarily drain structures of the **lower limb** and some external genital areas, but not the cervix directly. - They are located deeper in the groin region, distinct from the internal pelvic drainage. *Superficial inguinal lymph nodes* - These nodes drain the **skin of the lower abdomen**, perineum, and external genitalia, as well as the lower limbs. - They do not receive direct lymphatic drainage from the **cervix**.

Q: What is the lower limit of the retropharyngeal space?

Bifurcation of trachea. Bifurcation of trachea - The retropharyngeal space extends inferiorly to approximately the level of T4-T5 vertebrae, corresponding to the bifurcation of the trachea and the superior mediastinum. - This space lies between the buccopharyngeal fascia (posterior to pharynx) and the alar layer of prevertebral fascia. - Clinically, infections or abscesses in this space can descend into the posterior mediastinum, making knowledge of this inferior extent crucial for surgical management. - Note: Some anatomical texts describe the space ending at T1-T2, but for clinical and surgical purposes, the functional inferior limit extends to the bifurcation of the trachea. C7 - While some texts describe the retropharyngeal space as terminating around C7 (level of the lower border of cricoid cartilage), this represents the narrower definition. - The clinical and surgical definition extends the space further inferiorly to allow for tracking of infections into the chest. - C7 alone does not represent the accepted lower limit for examination purposes. 4th esophageal constriction - The fourth esophageal constriction is not a standard anatomical landmark (esophagus has 3-4 constrictions depending on classification). - Esophageal constrictions are luminal narrowings within the esophagus itself and do not define the boundaries of the retropharyngeal space, which is a fascial space posterior to both pharynx and esophagus. None of the options - This is incorrect because bifurcation of the trachea is the recognized lower limit of the retropharyngeal space for clinical and examination purposes. - Understanding this anatomical boundary is essential for predicting the spread of deep neck space infections.

Q: Maxillary bone does not articulate with:

Ethmoid. ***Ethmoid (Marked Correct - PYQ 2012)*** - This question reflects traditional teaching where the **maxilla-ethmoid articulation** was considered minimal or indirect. - In modern anatomy, the **maxilla DOES articulate with the ethmoid bone** via the uncinate process of the ethmoid and the medial wall of the maxillary sinus. - However, per the **NEET-PG 2012 answer key**, ethmoid was accepted as the correct answer, likely because this articulation is small and often not emphasized in basic anatomy teaching. - The maxilla has major articulations with: frontal, zygomatic, nasal, lacrimal, palatine, inferior nasal concha, vomer, and contralateral maxilla. *Sphenoid* - The **maxilla clearly articulates** with the **greater wing of the sphenoid bone** at the inferior orbital fissure. - This articulation is substantial and forms the posterolateral floor of the orbit. - The sphenoid-maxillary articulation contributes to the boundaries of the **pterygopalatine fossa**. *Frontal* - The **maxilla articulates extensively** with the **frontal bone** at the frontomaxillary suture. - This articulation forms the medial orbital rim and part of the anterior cranial floor interface. - This is one of the most prominent maxillary articulations. *Lacrimal* - The **maxilla articulates directly** with the **lacrimal bone**, forming the anterior part of the medial orbital wall. - Together they form the **lacrimal groove** which houses the lacrimal sac. - This articulation is essential for the nasolacrimal drainage pathway.

Q: The thyrocervical trunk is a branch of which part of subclavian artery?

1st part. ***1st part*** - The **thyrocervical trunk** is one of the three primary branches arising from the **first part** of the subclavian artery. - The first part lies medial to the **anterior scalene muscle**. *2nd part* - The **second part** of the subclavian artery gives rise to the **costocervical trunk**. - This part lies posterior to the **anterior scalene muscle**. *3rd part* - The **third part** of the subclavian artery typically has no branches or may give off the **dorsal scapular artery**. - This part lies lateral to the **anterior scalene muscle**. *4th part* - This option is incorrect as the **subclavian artery has only three parts**, divided by their relationship to the anterior scalene muscle. - There is no anatomical fourth part of the subclavian artery.

Q: What is the typical length of a human sperm cell?

55 micrometers. ***55 micrometers*** - A typical **human sperm cell** measures approximately **55 micrometers** from the head to the tip of the tail [1]. - This length allows for efficient motility and navigation within the female reproductive tract to reach the ovum [1]. *100 micrometers* - This length is significantly **longer** than the average size of a human sperm cell. - While some cells can achieve this size, it is not typical for **spermatozoa**. *65 micrometers* - Although closer to the actual size, **65 micrometers** is generally considered slightly larger than the average human sperm cell length. - Sperm length is critical for understanding their **mobility** and **fertility** [1]. *50 micrometers* - This measurement is slightly **shorter** than the typical length of a human sperm cell. - The precise length, including the **head** and **flagellum**, contributes to its function.

Q: Which of the following cell types is neuroectodermal in origin?

Smooth muscle cells. ***Smooth muscle cells*** - This is the **correct answer** based on a **specific exception**: smooth muscle cells of the **iris dilator and sphincter muscles** and the **ciliary muscle** in the eye are derived from **neuroectoderm** (specifically from the **optic cup**, an outgrowth of the neural tube). - **Important note:** The vast majority of smooth muscle in the body is of **mesodermal origin** (e.g., in blood vessels, GI tract, respiratory tract). This question tests knowledge of this **notable embryological exception**. - In the context of the given options, this is the only cell type with any neuroectodermal component. *Skeletal muscle cells* - Skeletal muscle cells are entirely derived from the **paraxial mesoderm**, specifically from **somites** (myotome portion). - They form the voluntary muscles of the body and are **never** of neuroectodermal origin. *Endothelial cells* - Endothelial cells lining blood vessels and lymphatic vessels are derived from the **mesoderm** (specifically from **angioblasts**). - They are part of the cardiovascular system and are **entirely mesodermal** in origin. *Cardiac muscle cells* - Cardiac muscle cells are derived from the **splanchnic mesoderm** (lateral plate mesoderm). - The heart musculature is **entirely mesodermal** with no neuroectodermal contribution. **Clinical Pearl:** Classic neuroectodermal derivatives include neurons, glial cells (astrocytes, oligodendrocytes), ependymal cells, and neural crest derivatives (Schwann cells, melanocytes, chromaffin cells). The smooth muscle of the iris represents an important exception to the general rule that smooth muscle is mesodermal.

Q: What is the preferred site for intramuscular injection in the gluteus muscle?

Superolateral. ***Superolateral*** - This quadrant is preferred because it avoids the **sciatic nerve** and major **blood vessels**, minimizing the risk of injury. - The muscle mass in this region, primarily the **gluteus medius**, is sufficient for medication absorption. *Inferomedial* - This area carries a high risk of damaging the **sciatic nerve**, which runs through the lower, medial part of the gluteus. - Injecting here can also hit major **blood vessels**, leading to bleeding or hematoma. *Superomedial* - While somewhat safer than the inferomedial quadrant, this area is still closer to the **sciatic nerve** exit point and major vessels compared to the superolateral region. - The muscle bulk is also less prominent here compared to the superolateral aspect. *Inferolateral* - This quadrant is still in the vicinity of the **sciatic nerve** and major blood vessels, making it riskier than the superolateral site. - There is less muscle mass here compared to the superior quadrants, which can lead to improper drug absorption.

Q: Which nerve primarily supplies the cervical esophagus?

Vagus. ***Vagus*** - The **vagus nerve** (cranial nerve X) provides parasympathetic innervation to the entire esophagus, including the cervical portion, through its branches. - For the **cervical esophagus** specifically, the vagus nerve supplies it via the **recurrent laryngeal nerve branches**, which provide motor innervation to the striated muscle in this region. - The vagus is considered the primary nerve because the recurrent laryngeal nerves are its direct branches, and the vagus coordinates overall esophageal function throughout its length. *Left recurrent laryngeal nerve* - The **left recurrent laryngeal nerve** is a branch of the vagus nerve that provides motor innervation to both the intrinsic muscles of the **larynx** and the **cervical esophagus**. - While it does directly supply the cervical esophagus with motor fibers, it is anatomically a branch of the vagus nerve rather than an independent primary supply. - In this context, the parent nerve (vagus) is considered the primary supply. *Right recurrent laryngeal nerve* - The **right recurrent laryngeal nerve** is also a branch of the vagus nerve that supplies both the laryngeal muscles and contributes to **cervical esophageal innervation**. - Like the left recurrent laryngeal nerve, it is a branch rather than the primary nerve source. - Both recurrent laryngeal nerves work as vagal branches to innervate the cervical esophagus. *Phrenic nerve* - The **phrenic nerve** (arising from C3-C5) primarily innervates the **diaphragm**, controlling respiration. - It does not supply the cervical esophagus and has no role in esophageal motility.

Q: Which of the following is not a boundary of the triangle of auscultation?

Rhomboid major. ***Rhomboid major*** - The **rhomboid major** muscle forms the **floor** of the triangle of auscultation, not one of its boundaries. - Its function is to **retract** and **rotate** the scapula, anchoring it to the thoracic wall. *Trapezius* - The **trapezius** muscle forms the **superior** and **medial** boundary of the triangle of auscultation. - It defines the upper limit of this anatomical space on the back. *Scapula* - The **medial border of the scapula** forms the **lateral** boundary of the triangle of auscultation. - This bony landmark helps to delineate the outer edge of the triangle. *Latissimus dorsi* - The **latissimus dorsi** muscle forms the **inferior** boundary of the triangle of auscultation. - It defines the lower limit of this region, allowing for better sound transmission to the thoracic cavity.

Q: Which structure is located immediately posterior to the head of the pancreas?

Portal vein. ***Portal vein*** - The **portal vein** is formed by the union of the **splenic vein** and the **superior mesenteric vein** (SMV) posterior to the **neck** of the pancreas [1]. - It then runs in a **groove on the posterior surface** of the head of the pancreas, lying anterior to the **inferior vena cava** (IVC). - Among the given options, the portal vein has the most direct posterior relationship to the head of the pancreas. *Splenic artery* - The **splenic artery** runs along the **superior border** of the pancreas, following its body and tail. - It does not lie posterior to the head of the pancreas. - It is a branch of the **celiac trunk** and supplies the spleen. *Inferior mesenteric vein* - The **inferior mesenteric vein** typically drains into the **splenic vein** or the junction of the splenic and superior mesenteric veins. - It ascends **anterior** to the left kidney and does not lie immediately posterior to the head of the pancreas. *Coeliac trunk* - The **celiac trunk** originates from the **abdominal aorta** at the level of T12-L1 vertebra. - It lies **superior and anterior** to the pancreas, giving off the splenic artery, common hepatic artery, and left gastric artery. - It is not located posterior to the head of the pancreas.

Question 1

Lymphatic drainage of cervix is to

Accepted Answer

Iliac lymph nodes

Answer

Para-aortic lymph nodes

Answer

Deep inguinal lymph nodes

Answer

Superficial inguinal lymph nodes

Question 2

What is the lower limit of the retropharyngeal space?

Accepted Answer

Bifurcation of trachea

Answer

4th esophageal constriction

Answer

C7

Answer

None of the options

Question 3

Maxillary bone does not articulate with:

Accepted Answer

Ethmoid

Answer

Frontal

Answer

Lacrimal

Answer

Sphenoid

Question 4

The thyrocervical trunk is a branch of which part of subclavian artery?

Accepted Answer

1st part

Answer

2nd part

Answer

3rd part

Answer

4th part

Question 5

What is the typical length of a human sperm cell?

Accepted Answer

55 micrometers

Answer

50 micrometers

Answer

100 micrometers

Answer

65 micrometers

Question 6

Which of the following cell types is neuroectodermal in origin?

Accepted Answer

Smooth muscle cells

Answer

Skeletal muscle cells

Answer

Endothelial cells

Answer

Cardiac muscle cells

Question 7

What is the preferred site for intramuscular injection in the gluteus muscle?

Accepted Answer

Superolateral

Answer

Inferolateral

Answer

Superomedial

Answer

Inferomedial

Question 8

Which nerve primarily supplies the cervical esophagus?

Accepted Answer

Vagus

Answer

Left recurrent laryngeal nerve

Answer

Right recurrent laryngeal nerve

Answer

Phrenic nerve

Question 9

Which of the following is not a boundary of the triangle of auscultation?

Accepted Answer

Rhomboid major

Answer

Trapezius

Answer

Scapula

Answer

Latissimus dorsi

Question 10

Which structure is located immediately posterior to the head of the pancreas?

Accepted Answer

Portal vein

Answer

Splenic artery

Answer

Inferior mesenteric vein

Answer

Coeliac trunk

NEET-PG 2012 — Anatomy