NEET-PG 2013 Practice Questions

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: Sacral promontory is the landmark for

Termination of presacral nerve. ***Termination of presacral nerve*** - The **sacral promontory** is the key anatomical landmark where the **superior hypogastric plexus** (presacral nerve) **bifurcates** into the right and left hypogastric nerves. - This bifurcation typically occurs at the level of the **sacral promontory**, making it a crucial landmark for **presacral neurectomy** procedures. - The superior hypogastric plexus is formed by the fusion of sympathetic fibers and lies anterior to the L5 vertebra and sacral promontory. - Clinically important for **pelvic surgery** and **pain management** procedures. *Origin of superior mesenteric artery* - The **superior mesenteric artery (SMA)** originates from the **anterior aspect of the abdominal aorta** at the level of the **L1 vertebra**. - This is far superior to the sacral promontory, which is at the lumbosacral junction (L5-S1). - The SMA supplies the midgut derivatives. *Origin of inferior mesenteric artery* - The **inferior mesenteric artery (IMA)** originates from the **anterior aspect of the abdominal aorta** at the level of the **L3 vertebra**. - This is also well above the sacral promontory. - The IMA supplies the hindgut derivatives. *None of the options* - This is incorrect as the sacral promontory is indeed a recognized landmark for the **bifurcation/termination of the presacral nerve** (superior hypogastric plexus).

Q: Which muscle is attached to the lateral surface of the greater trochanter?

Gluteus medius. ***Gluteus medius*** - The **gluteus medius** inserts onto the **lateral surface of the greater trochanter** of the femur. - Its primary actions include **abduction** and **internal rotation** of the hip. *Gluteus maximus* - The **gluteus maximus** inserts primarily into the **iliotibial tract** and the **gluteal tuberosity** of the posterior femur, not the lateral greater trochanter. - Its main roles are **hip extension** and **external rotation**. *Gluteus minimus* - The **gluteus minimus** inserts onto the **anterior part of the lateral surface (anterolateral aspect)** of the greater trochanter, anterior to the gluteus medius insertion. - Like the gluteus medius, it also contributes to **hip abduction** and **internal rotation**. *Piriformis* - The **piriformis** muscle inserts onto the **superior and medial aspect of the greater trochanter**. - Its main actions are **external rotation** and **abduction** of the hip, particularly when the hip is flexed.

Q: Esophagus is present in which mediastinum?

Posterior. ***Posterior*** - The **esophagus** is primarily located in the **posterior mediastinum**, where the bulk of its length (from T4/T5 to T10) traverses [2]. - It lies **posterior** to the **trachea** and **heart**, anterior to the vertebral column [2]. - For examination purposes, the esophagus is considered a **key structure of the posterior mediastinum** [2]. - Note: The uppermost part (cervical and upper thoracic) does pass through the superior mediastinum, but the majority lies in the posterior compartment. *Anterior* - The **anterior mediastinum** is a small space located between the **sternum** and the pericardium. - It primarily contains **connective tissue**, remnants of the thymus, lymph nodes, and the internal thoracic vessels [1]. - The esophagus does not traverse this compartment. *Middle* - The **middle mediastinum** is centrally located and prominently contains the **heart** and the roots of the great vessels [1]. - It also houses the **pericardium**, the main bronchi, and the phrenic nerves [1]. - The esophagus passes **posterior** to this compartment, not through it. *Superior* - The **superior mediastinum** extends from the thoracic inlet to the level of the sternal angle (T4/T5). - It contains large vessels like the **aortic arch** and its branches, the SVC, trachea, and thymus [1]. - While the **uppermost part of the thoracic esophagus** does pass through the superior mediastinum, this represents only a small portion of its total length.

Q: What is the approximate ratio of connective tissue to smooth muscle in the cervix?

Approximately 8:1. ***Approximately 8:1*** - The **cervix** is predominantly composed of **fibrous connective tissue**, which provides its structural integrity and rigidity [1]. - This high ratio of **collagenous connective tissue** to smooth muscle is crucial for maintaining pregnancy and undergoing significant remodeling during parturition [1]. - The approximate ratio is **8:1 to 10:1**, with connective tissue forming about 85-90% of cervical tissue [1]. *2:1* - This ratio would imply a significantly higher proportion of **smooth muscle** (33%), making the cervix much more muscular and less fibrous than it actually is. - Such a composition would compromise the cervical function of maintaining a **closed uterine orifice** during pregnancy. *5:1* - While higher than 2:1, this ratio still underestimates the true dominance of **connective tissue** in the cervical structure. - The **cervix's mechanical properties**, including its ability to resist stretching, are primarily due to its abundant collagen content. *15:1* - This ratio overestimates the proportion of connective tissue, suggesting less than 7% smooth muscle. - While the cervix is indeed fibrous, it does contain a modest amount of **smooth muscle** (10-15%) particularly in the internal os region, making this ratio too extreme [1].

Q: Which of the following statements about the great saphenous vein is true?

It runs anterior to medial malleolus. **It runs anterior to medial malleolus** - The **great saphenous vein** originates from the medial end of the **dorsal venous arch** of the foot and ascends anterior to the **medial malleolus** [1]. - This anatomical relationship makes it accessible for various clinical procedures, such as **venous cutdown** for rapid intravenous access [1]. *It begins at lateral end of dorsal venous arch* - The **great saphenous vein** actually begins at the **medial end** of the dorsal venous arch, not the lateral end [1]. - The **small saphenous vein** arises from the lateral end of the dorsal venous arch [1]. *It is accompanied by the sural nerve* - The **sural nerve** typically accompanies the **small saphenous vein**, not the great saphenous vein, in the posterior leg [1]. - The **saphenous nerve**, a branch of the femoral nerve, accompanies the great saphenous vein throughout its course in the leg. *Terminates into popliteal vein* - The **great saphenous vein** normally terminates by draining into the **femoral vein** in the femoral triangle, not the popliteal vein [1]. - The **small saphenous vein** is the one that typically drains into the popliteal vein [1].

Q: What is the nerve supply to the muscles of the flexor compartment of the arm?

Musculocutaneous nerve. ***Musculocutaneous nerve*** - The **musculocutaneous nerve** is the primary nerve supplying all three muscles in the **flexor compartment of the arm**: the **biceps brachii**, **brachialis**, and **coracobrachialis**. - Its motor branches innervate these muscles, allowing for **flexion at the elbow** and **supination of the forearm**. *Median nerve* - The **median nerve** primarily innervates most muscles in the **flexor compartment of the forearm**, not the arm. - It plays a crucial role in **wrist and finger flexion**, as well as movements of the **thenar eminence**. *Radial nerve* - The **radial nerve** is the main nerve for the **extensor compartment of the arm and forearm**. - It is responsible for **elbow, wrist, and finger extension**. *Ulnar nerve* - The **ulnar nerve** primarily supplies intrinsic muscles of the hand and some flexor muscles in the forearm. - It has no motor supply to the muscles of the **flexor compartment of the arm**.

Q: Which is the primary muscle causing supination of the forearm?

Supinator. ***Supinator*** - The **supinator muscle** is the **primary muscle** responsible for **supination** of the forearm, rotating the palm anteriorly or superiorly. - It is a deep muscle of the **posterior compartment** of the forearm. - Its action is especially prominent when **supinating against resistance** or in very slow movements, as it works synergistically with the biceps brachii. *Biceps brachii* - While the **biceps brachii** is also a powerful **supinator** of the forearm, especially when the elbow is flexed, it is a **secondary supinator**. - It is primarily a major **flexor** of the elbow, whereas the supinator is dedicated specifically to supination. *Brachioradialis* - The **brachioradialis** is primarily a **flexor** of the forearm at the elbow joint. - It helps to bring the forearm into a **mid-prone or mid-supine position** from either full pronation or full supination, but does not actively supinate. *Anconeus* - The **anconeus** is a small muscle that assists the **triceps brachii** in **extension of the forearm** at the elbow. - It helps to **stabilize the elbow joint** and slightly abducts the ulna during pronation, but has no role in supination.

Q: Which muscles are known as 'Triceps surae'?

Gastro-soleus. ***Gastro-soleus*** - The **Triceps surae** refers to the two heads of the **gastrocnemius muscle** and the **soleus muscle**, which together form the powerful calf muscle. - These three muscles converge to form the **Achilles tendon** (calcaneal tendon) and are prime movers for **plantarflexion** of the ankle. *Popliteus* - The popliteus muscle is located behind the knee joint and acts to **unlock the knee** during flexion. - It does not contribute to the bulk of the calf and is not part of the Triceps surae group. *Extensor hallucis longus* - This muscle is located in the **anterior compartment** of the leg and is responsible for **dorsiflexion** of the ankle and extension of the great toe. - It is an antagonist to the Triceps surae, which primarily performs plantarflexion. *Extensor digitorum longus* - The extensor digitorum longus is also in the **anterior compartment** of the leg, responsible for **dorsiflexion** of the ankle and extension of the lateral four toes. - It is functionally opposite to the actions of the Triceps surae and in a different muscle compartment.

Q: At what age does the tonic neck reflex typically disappear?

4 months. ***Correct Answer: 4 months*** - The **tonic neck reflex**, also known as the **asymmetrical tonic neck reflex (ATNR)**, typically disappears around **4 to 6 months of age**. - Persistence beyond this age can be a sign of **neurological dysfunction** and may interfere with motor development such as rolling or bringing hands to midline. *Incorrect: 1 month* - While the tonic neck reflex is present at 1 month, it does not typically disappear at this early stage. - At 1 month, infants are still relying on a variety of **primitive reflexes** for survival and early motor patterns. *Incorrect: 2 months* - The tonic neck reflex is still usually clearly present at 2 months of age. - This reflex contributes to early **eye-hand coordination** and helps develop unilateral body movements. *Incorrect: 3 months* - While starting to integrate, the tonic neck reflex is not fully integrated or gone by 3 months. - Its presence is normal at this age, and its integration is a gradual process as **voluntary motor control** emerges.

Question 1

Which organ is primarily supplied by the portal vein?

Accepted Answer

Liver

Answer

Spleen

Answer

Pancreas

Answer

Colon

Question 2

Sacral promontory is the landmark for

Accepted Answer

Termination of presacral nerve

Answer

None of the options

Answer

Origin of inferior mesenteric artery

Answer

Origin of superior mesenteric artery

Question 3

Which muscle is attached to the lateral surface of the greater trochanter?

Accepted Answer

Gluteus medius

Answer

Gluteus maximus

Answer

Gluteus minimus

Answer

Piriformis

Question 4

Esophagus is present in which mediastinum?

Accepted Answer

Posterior

Answer

Answer

Middle

Answer

Superior

Question 5

What is the approximate ratio of connective tissue to smooth muscle in the cervix?

Accepted Answer

Approximately 8:1

Answer

2:1

Answer

5:1

Answer

15:1

Question 6

Which of the following statements about the great saphenous vein is true?

Accepted Answer

It runs anterior to medial malleolus

Answer

It begins at lateral end of dorsal venous arch

Answer

Terminates into popliteal vein

Answer

It is accompanied by the sural nerve

Question 7

What is the nerve supply to the muscles of the flexor compartment of the arm?

Accepted Answer

Musculocutaneous nerve

Answer

Median nerve

Answer

Radial nerve

Answer

Ulnar nerve

Question 8

Which is the primary muscle causing supination of the forearm?

Accepted Answer

Supinator

Answer

Brachioradialis

Answer

Anconeus

Answer

Biceps brachii

Question 9

Which muscles are known as 'Triceps surae'?

Accepted Answer

Gastro-soleus

Answer

Popliteus

Answer

Extensor hallucis longus

Answer

Extensor digitorum longus

Question 10

At what age does the tonic neck reflex typically disappear?

Accepted Answer

4 months

Answer

1 month

Answer

2 months

Answer

3 months

NEET-PG 2013

Anatomy

Pediatrics