NEET-PG 2013 Practice Questions

Q: Which muscle plays a role in winking?

Orbicularis oculi. ***Orbicularis oculi*** - This muscle is responsible for **closing the eyelid** and is essential for actions like blinking, squinting, and winking. - Its fibers encircle the eye and facilitate the **controlled closure** required for winking. *Levator labii superioris* - This muscle primarily functions to **elevate the upper lip**, playing a role in facial expressions such as sneering or smiling. - It has no direct involvement in the movement of the eyelids or the act of winking. *Corrugator supercilii* - This muscle is located in the eyebrow region and is responsible for **drawing the eyebrows medially and inferiorly**, creating vertical wrinkles between the eyebrows. - It is associated with expressions of frowning or concern, not eyelid closure. *Levator palpebrae* - This muscle is responsible for **opening the upper eyelid**, thus counteracting the action of the orbicularis oculi. - While essential for eye movement, it is not involved in the closing action required for winking.

Q: Which organ is primarily supplied by the portal vein?

Liver. ***Liver*** - The **portal vein** is unique in that it carries **nutrient-rich, deoxygenated blood** from the gastrointestinal tract and spleen directly to the liver [1], [2]. - This specialized circulation allows the liver to **process absorbed nutrients** and detoxify harmful substances before they enter the systemic circulation [1], [3]. *Spleen* - The spleen is supplied by the **splenic artery**, a branch of the **celiac trunk**, which carries oxygenated arterial blood to the organ. - While the splenic vein drains into the portal vein, the portal vein itself does not primarily supply the spleen [2]. *Pancreas* - The pancreas receives its blood supply from branches of the **celiac artery** and the **superior mesenteric artery**, specifically the splenic, gastroduodenal, and superior mesenteric arteries [1]. - While pancreatic veins drain into the portal system, the portal vein is not the primary arterial supply to the pancreas [1]. *Colon* - The colon is supplied by the **superior mesenteric artery** and the **inferior mesenteric artery**, which provide oxygenated arterial blood to different segments of the large intestine. - The venous drainage from the colon primarily collects into the superior and inferior mesenteric veins, which then merge to form part of the portal venous system, but the portal vein does not primarily supply the colon with blood [2].

Q: What is the typical length of the anal canal in adults?

35 - 40 mm. ***35 - 40 mm*** - The **anal canal** in adults typically measures between **3.5 to 4.0 cm** (35 to 40 mm) in length. - This length is measured from the **anorectal ring** to the **anal verge**. *10 - 15 mm* - This length is too short for the **adult anal canal**; it's approximately one-third of the actual length. - Such a short measurement would be anatomically incorrect and clinically significant for various colorectal conditions. *15 - 20 mm* - This measurement is still significantly shorter than the average length of the **adult anal canal**. - A canal this short would likely be pathological or developmental in origin. *25 - 30 mm* - While closer, this range is still generally below the accepted average length of the **adult anal canal**. - Precise anatomical measurements are crucial for diagnostic and surgical procedures in proctology.

Q: Upper two posterior intercostal arteries arise from ?

Superior intercostal artery. ***Superior intercostal artery*** - The **superior intercostal artery** is a branch of the **costocervical trunk**, which itself arises from the subclavian artery. - It supplies the **first two posterior intercostal spaces**, hence the "upper two" mentioned in the question. *Aorta* - The **descending thoracic aorta** directly supplies the posterior intercostal arteries from the **3rd to the 11th intercostal spaces**. - It does not, however, supply the first two posterior intercostal arteries. *Internal mammary artery* - The **internal mammary artery** (also known as the internal thoracic artery) supplies the **anterior intercostal arteries** [1]. - It arises from the **subclavian artery** [1] but is not involved in supplying the posterior intercostal spaces. *Bronchial artery* - **Bronchial arteries** primarily supply the **lungs and bronchi**, providing oxygenated blood to the lung tissue. - They are not the main source of blood supply for the intercostal spaces.

Q: What is the nerve supply of the larynx above the level of the vocal cords?

Superior laryngeal. ***Superior laryngeal*** - The **superior laryngeal nerve** branches into the internal and external laryngeal nerves. The **internal laryngeal nerve** (a branch of the superior laryngeal nerve) provides all sensory innervation to the larynx **above the vocal cords**. - It also carries **parasympathetic fibers** to the laryngeal glands in this region. *Recurrent laryngeal* - The **recurrent laryngeal nerve** provides sensory innervation to the larynx **below the vocal cords** [1]. - It also innervates all of the intrinsic muscles of the larynx except for the cricothyroid muscle [1]. *Glossopharyngeal* - The **glossopharyngeal nerve (CN IX)** primarily provides sensory innervation to the **posterior one-third of the tongue**, tonsils, pharynx, and middle ear. - It does not directly provide sensory innervation to the larynx. *External laryngeal nerve* - The **external laryngeal nerve**, a branch of the superior laryngeal nerve, is primarily **motor** and innervates the **cricothyroid muscle**. - It provides **no sensory innervation** to any part of the larynx.

Q: All pass through jugular foramen except

Mandibular nerve. ***Mandibular nerve*** - The **mandibular nerve** (CN V3) exits the skull through the **foramen ovale**, not the jugular foramen. - It is a branch of the **trigeminal nerve** and is responsible for motor innervation to muscles of mastication and sensory innervation to the lower face and mouth. *Glossopharyngeal nerve* - The **glossopharyngeal nerve** (CN IX) is one of the three cranial nerves that exit through the **jugular foramen**. - It provides motor, sensory, and parasympathetic innervation including taste from posterior third of tongue and motor to stylopharyngeus muscle. *Vagus nerve* - The **vagus nerve** (CN X) is one of the major cranial nerves that exits the skull through the **jugular foramen**. - It provides extensive motor, sensory, and parasympathetic innervation to the head, neck, thorax, and abdomen. *Internal jugular vein* - The **internal jugular vein** is formed at the jugular foramen by the continuation of the **sigmoid sinus**, and it exits the skull through this foramen. - It is one of the primary venous drainage pathways for the brain.

Q: The roof of the olfactory region is formed by?

Cribriform plate of ethmoid. ***Cribriform plate of ethmoid*** - The **cribriform plate** of the ethmoid bone forms the superior boundary, or roof, of the nasal cavity specifically in the olfactory region [1]. - It is perforated by numerous **olfactory foramina** through which the olfactory nerves pass from the nasal cavity to the olfactory bulb of the brain [2]. *Nasal bone* - The **nasal bones** form part of the bridge of the nose and contribute to the anterior part of the bony framework of the external nose. - They do not form the roof of the olfactory region within the nasal cavity. *Sphenoid* - The **sphenoid bone** is a complex bone at the base of the skull, contributing to the posterior wall of the nasal cavity and parts of the cranial floor. - It does not directly form the roof of the olfactory region. *Temporal bone* - The **temporal bones** are located on the sides and base of the skull, housing structures related to hearing and balance. - They are not involved in forming the roof of the nasal cavity or the olfactory region.

Q: What is a cochleate uterus?

Acute anteflexion. ***Acute anteflexion*** - A **cochleate uterus** describes a uterus with an **acute anteflexion**, meaning it is sharply bent forward at the junction of the cervix and the body of the uterus. - This anatomical variation can sometimes be associated with **dysmenorrhea** or difficulty with **intrauterine device (IUD) insertion**. *Large uterus* - A large uterus, also known as **uteromegaly**, is a general descriptive term for an enlarged uterus, which can be due to various causes such as **fibroids** or **adenomyosis**, and is not specific to an acute anteflexion. - It does not directly describe the acute angulation that defines a cochleate uterus. *Acute retroflexion* - **Acute retroflexion** refers to a uterus that is sharply bent backward at the level of the cervix. - This is the opposite of **anteflexion**, which describes a forward bend, and therefore is not a cochleate uterus. *Large cervix* - A **large cervix** describes an enlarged uterine cervix, which is the lower, narrow part of the uterus. - This typically relates to conditions like **cervical hypertrophy** or **nabothian cysts** and is distinct from the overall angulation of the uterine body in relation to the cervix.

Q: Hurthle cell carcinoma is a variant of which type of carcinoma?

Follicular carcinoma. **Follicular carcinoma** - **Hürthle cell carcinoma**, also known as **oxyphilic follicular carcinoma**, is a specific variant of **follicular carcinoma of the thyroid**. - It is characterized by the presence of large polygonal cells with abundant eosinophilic, granular cytoplasm known as **Hürthle cells** (or oxyphil cells) within the neoplastic growth. *Medullary carcinoma* - **Medullary carcinoma** originates from the **parafollicular C cells** of the thyroid, which produce calcitonin. - It is histologically distinct, featuring nests or cords of cells often associated with **amyloid deposits**, and is not related to Hürthle cell morphology. *Papillary carcinoma* - **Papillary carcinoma** is the most common type of thyroid cancer, characterized by distinctive **nuclear features** such as **Orphan Annie eye nuclei**, nuclear grooves, and intranuclear cytoplasmic inclusions. - Its histological origin and morphological appearance are different from Hürthle cell neoplasms, which are follicular in origin. *Anaplastic carcinoma* - **Anaplastic carcinoma** is a highly aggressive and undifferentiated thyroid malignancy with a very poor prognosis. - It is characterized by pleomorphic, giant, and spindle cells and lacks the specific differentiation seen in follicular or Hürthle cell tumors.

Q: Which route of administration undergoes the maximum first pass metabolism?

Oral. ***Oral*** - Drugs administered orally are absorbed from the **gastrointestinal tract** and transported via the **portal vein** directly to the liver, where they undergo significant **first-pass metabolism** before reaching systemic circulation. - This hepatic metabolism can drastically reduce the **bioavailability** of the drug, requiring higher doses or alternative administration routes. *Intra-arterial* - This route delivers drugs directly into an **artery** supplying a target tissue or organ, largely bypassing systemic circulation and initial hepatic metabolism. - It is used for localized effects, such as **chemotherapy** for specific tumors, minimizing systemic exposure. *Rectal* - While a portion of rectally administered drugs may bypass the portal circulation by entering the **inferior and middle rectal veins**, a significant amount can still be absorbed into the superior rectal vein, which drains into the portal system. - This means rectal administration offers only **partial avoidance** of first-pass metabolism, making it less complete than IV or intra-arterial routes for bypassing the liver altogether. *Intravenous* - Drugs administered intravenously are delivered directly into the **systemic circulation**, completely bypassing the gastrointestinal tract and the liver's first-pass metabolism. - This route ensures **100% bioavailability** and rapid onset of action, as the drug immediately reaches its target.

Question 1

Which muscle plays a role in winking?

Accepted Answer

Orbicularis oculi

Answer

Levator labii superioris

Answer

Levator palpebrae

Answer

Corrugator supercilii

Question 2

Which organ is primarily supplied by the portal vein?

Accepted Answer

Liver

Answer

Spleen

Answer

Pancreas

Answer

Colon

Question 3

What is the typical length of the anal canal in adults?

Accepted Answer

35 - 40 mm

Answer

10 - 15 mm

Answer

15 - 20 mm

Answer

25 - 30 mm

Question 4

Upper two posterior intercostal arteries arise from ?

Accepted Answer

Superior intercostal artery

Answer

Internal mammary artery

Answer

Bronchial artery

Answer

Aorta

Question 5

What is the nerve supply of the larynx above the level of the vocal cords?

Accepted Answer

Superior laryngeal

Answer

Recurrent laryngeal

Answer

Glossopharyngeal

Answer

External laryngeal nerve

Question 6

All pass through jugular foramen except

Accepted Answer

Mandibular nerve

Answer

Vagus nerve

Answer

Internal jugular vein

Answer

Glossopharyngeal nerve

Question 7

The roof of the olfactory region is formed by?

Accepted Answer

Cribriform plate of ethmoid

Answer

Nasal bone

Answer

Sphenoid

Answer

Temporal bone

Question 8

What is a cochleate uterus?

Accepted Answer

Acute anteflexion

Answer

Large uterus

Answer

Acute retroflexion

Answer

Large cervix

Question 9

Hurthle cell carcinoma is a variant of which type of carcinoma?

Accepted Answer

Follicular carcinoma

Answer

Medullary carcinoma

Answer

Papillary carcinoma

Answer

Anaplastic carcinoma

Question 10

Which route of administration undergoes the maximum first pass metabolism?

Accepted Answer

Oral

Answer

Intra-arterial

Answer

Rectal

Answer

Intravenous

NEET-PG 2013

Anatomy

Obstetrics and Gynecology

Pathology

Pharmacology