NEET-PG 2012 Practice Questions

Q: Nutrient artery runs ?

Away from epiphysis. ***Away from epiphysis*** - The **nutrient artery** runs away from the **dominant (faster-growing) epiphysis** towards the non-dominant end of the bone. - This follows the classic anatomical rule: **"To the elbow, from the knee"** - nutrient arteries point towards the elbow in upper limb bones and away from the knee in lower limb bones. - The **nutrient foramen** is directed obliquely away from the more actively growing end, established during bone development. - Examples: In the humerus, it runs towards the elbow (away from proximal epiphysis); in the femur, it runs away from the knee (away from distal epiphysis). *Towards metaphysis* - While the artery does course towards the metaphyseal region of the slower-growing end, this option is less anatomically precise. - The standard teaching emphasizes the relationship with the **dominant epiphysis** rather than the metaphysis. *Away from metaphysis* - This is **incorrect** - the nutrient artery actually runs **towards** the metaphysis of the non-dominant end. - It runs **away from** the dominant epiphysis, not away from the metaphysis. *None of the options* - This is incorrect as **"Away from epiphysis"** correctly describes the direction of the nutrient artery relative to the dominant growing end.

Q: Pituicytes are seen in ?

Posterior lobe. ***Posterior lobe*** - **Pituicytes** are specialized glial cells found exclusively in the **posterior pituitary** (neurohypophysis). [1] - They provide structural support and regulation for the nerve terminals that release **antidiuretic hormone (ADH)** and **oxytocin**. [1] *Anterior lobe* - The anterior pituitary, or **adenohypophysis**, consists of glandular epithelial cells that synthesize and secrete various hormones. [2] - It does not contain pituicytes, which are glial cells. [2] *Intermediate lobe* - The intermediate lobe is a rudimentary part of the pituitary gland in humans, primarily producing **melanocyte-stimulating hormone (MSH)**. [1] - While it is part of the pituitary, it does not contain pituicytes. *All of the options* - Pituicytes are specific to the posterior pituitary, so they are not found in all parts of the gland. - Different lobes of the pituitary gland have distinct cellular compositions and functions.

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: Anal valve is found in which part of anal canal?

Middle. ***Middle*** - The **anal valves** are crescentic folds located at the level of the **pectinate (dentate) line** in the middle portion of the anal canal. - They mark the inferior limit of the **anal columns** and form small recesses called **anal sinuses**. *Lower* - The lower part of the anal canal, below the pectinate line, is lined by **anoderm** and lacks anal valves. - This region is sensitive to pain due to somatic innervation. *At anus* - The anus refers to the external opening and perianal skin, which does not contain anal valves. - The anal canal transitions into the perianal skin at the anocutaneous line. *Upper* - The upper part of the anal canal, above the pectinate line, contains the **anal columns (columns of Morgagni)** but not the anal valves themselves, which are located at the base of these columns. - This region is lined by columnar epithelium and is relatively insensitive to pain.

Q: In patients with penile or urethral injury, Colle's fascia prevents extravasation of urine from spreading into which anatomical space?

Ischiorectal fossa. ***Ischiorectal fossa*** - Colle's fascia (superficial perineal fascia) is the membranous layer that defines the boundaries of the **superficial perineal space**. - When urethral injury occurs, urine extravasates into the superficial perineal space but is **prevented from spreading laterally and posteriorly** into the ischiorectal fossa because Colle's fascia fuses with the **ischiopubic rami** laterally and the **perineal membrane** posteriorly [1]. - The ischiorectal fossa is a space lateral to the **anal canal** that is separated from the superficial perineal space by these fascial attachments. *Superficial perineal space* - This is actually the space **into which** urine extravasates when penile or urethral injury occurs, not the space that is protected from extravasation [1]. - Colle's fascia forms the inferior boundary of this space, so urine collects here rather than being prevented from entering. *Abdomen* - Colle's fascia in the perineum is continuous with **Scarpa's fascia** of the anterior abdominal wall. - Due to this continuity, urine can actually **track superiorly** into the anterior abdominal wall along this fascial plane. - Therefore, Colle's fascia does NOT prevent spread to the abdomen. *None of the options* - This option is incorrect because Colle's fascia specifically prevents lateral and posterior spread into the ischiorectal fossa through its anatomical attachments.

Q: Which of the following structures is not derived from the ectoderm?

Eustachian tube. ***Eustachian tube*** - The **Eustachian tube** (auditory tube) is derived from the **endoderm**, specifically from the first pharyngeal pouch. - It connects the nasopharynx to the middle ear and is responsible for equalizing pressure [1]. *Lens* - The **lens** of the eye develops from the surface ectoderm through an invagination called the **lens placode**. - This ectodermal origin is crucial for its transparency and refractive properties. *Brain* - The **brain** is a primary derivative of the ectoderm, specifically the **neural tube**, which forms from the neural plate during neurulation. - This ectodermal origin gives rise to the entire central nervous system. *Retina* - The **retina** of the eye, along with the optic nerve, develops from the **neuroectoderm** (a part of the neural tube). - Its ectodermal origin is essential for its light-sensing function.

Q: Which of the following is not a boundary of Koch's triangle?

Limbus fossa ovalis. ***Limbus fossa ovalis*** - The **limbus fossa ovalis** is a prominent oval ridge on the **interatrial septum** that surrounds the fossa ovalis. - It is **not involved** in forming the boundaries of Koch's triangle, which is located in the **right atrium** near the AV node [1]. *Tricuspid valve ring* - The **tricuspid valve ring** (or annulus) forms one of the key anatomical boundaries of **Koch's triangle**, specifically its base [1]. - This **fibrous ring** anchors the tricuspid valve leaflets and marks the inferior aspect of the triangle [1]. *Coronary sinus* - The **coronary sinus ostium** (opening) forms another crucial boundary of **Koch's triangle** [1]. - It is located at the **inferior-posterior aspect** of the interatrial septum, opening into the right atrium [1]. *Tendon of todaro* - The **Tendon of Todaro** is a fibrous structure that forms the superior boundary of **Koch's triangle** [1]. - It extends from the **Eustachian valve** (of the inferior vena cava) towards the central fibrous body, playing a role in **AV nodal localization** [1].

Q: Which of the following is the most characteristic symptom of obstruction of the inferior vena cava?

Paraumblical dilatation. ***Paraumbilical dilatation*** - Obstruction of the **inferior vena cava (IVC)** leads to collateral circulation through superficial veins, especially around the umbilicus, causing **paraumbilical dilatation** (caput medusae). - This collateral flow bypasses the obstructed IVC to return blood to the superior vena cava system. *Thoraco-epigastric dilatation* - This pattern of collateral circulation is more characteristic of **superior vena cava (SVC) obstruction**, where blood from the upper body needs to bypass the SVC. - The dilated veins would typically be seen on the chest and upper abdomen, draining towards the femoral veins. *Oesophageal varices* - **Oesophageal varices** are typically caused by **portal hypertension** [1], often secondary to liver cirrhosis, not directly by IVC obstruction. - They represent portosystemic collateral veins, diverging from the portal system to the systemic circulation [1]. *Haemorrhoids* - **Haemorrhoids** are dilated veins in the anal canal, most commonly caused by **straining** during defecation or conditions that increase intra-abdominal pressure [2]. - While they can be a sign of portal hypertension [1], **IVC obstruction** is not their primary or most characteristic cause.

Q: What is the average progressive velocity of human sperm under standard laboratory conditions?

1-3 mm/min. ***1-3 mm/min*** - The typical average progressive velocity of human sperm, categorized as **Grade A (rapid progressive)** motility, ranges from **25 micrometers/second or faster**, which translates to approximately 1-3 mm/minute. - This velocity is crucial for sperm to traverse the female reproductive tract and reach the ovum for fertilization. *4-6 mm/min* - This velocity range is significantly faster than the **average progressive velocity** observed in viable human sperm under standard laboratory conditions. - While some individual sperm may achieve higher speeds, this range is not representative of the **average progressive motility** of a healthy sperm population. *6-9 mm/min* - This progressive velocity is exceptionally high and not typically observed as the average for human sperm, even for highly motile sperm. - Such a high velocity would indicate an **abnormally fast movement** not compatible with biological norms for average progressive motility. *10-13 mm/min* - This range represents an extremely rapid progressive velocity for human sperm, well beyond physiological averages. - It does not align with the standard measurements for **progressive motility**, which are generally much lower.

Q: Which of the following is an acquired condition?

Mastitis. ***Mastitis*** - **Mastitis** is an **inflammatory condition** of the breast, often caused by bacterial infection, particularly common during **lactation** [1]. - It is an **acquired condition** as it develops after birth due to external or internal factors, not present at birth. *Polymastia (supernumerary breasts)* - **Polymastia** is a **congenital condition** where additional breast tissue develops along the **milk line**. - This condition is present at birth and results from *embryological development anomalies*, not acquired later in life. *Polythelia (extra nipples)* - **Polythelia** refers to the presence of **accessory nipples** along the embryonic milk line and is a **congenital anomaly**. - Like polymastia, it is present from birth due to *developmental errors* and is not an acquired condition. *Amastia (absence of breast tissue)* - **Amastia** is a rare **congenital anomaly** characterized by the complete absence of breast tissue, nipple, and areola. - It is a **birth defect**, meaning it is present from birth and not an acquired condition.

Question 1

Nutrient artery runs ?

Accepted Answer

Away from epiphysis

Answer

Towards metaphysis

Answer

None of the options

Answer

Away from metaphysis

Question 2

Pituicytes are seen in ?

Accepted Answer

Posterior lobe

Answer

Anterior lobe

Answer

Intermediate lobe

Answer

All of the options

Question 3

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 4

Anal valve is found in which part of anal canal?

Accepted Answer

Middle

Answer

Lower

Answer

At anus

Answer

Upper

Question 5

In patients with penile or urethral injury, Colle's fascia prevents extravasation of urine from spreading into which anatomical space?

Accepted Answer

Ischiorectal fossa

Answer

Superficial perineal space

Answer

None of the options

Answer

Abdomen

Question 6

Which of the following structures is not derived from the ectoderm?

Accepted Answer

Eustachian tube

Answer

Brain

Answer

Retina

Answer

Lens

Question 7

Which of the following is not a boundary of Koch's triangle?

Accepted Answer

Limbus fossa ovalis

Answer

Tricuspid valve ring

Answer

Coronary sinus

Answer

Tendon of Todaro

Question 8

Which of the following is the most characteristic symptom of obstruction of the inferior vena cava?

Accepted Answer

Paraumblical dilatation

Answer

Thoraco-epigastric dilatation

Answer

Haemorrhoides

Answer

Oesophageal varices

Question 9

What is the average progressive velocity of human sperm under standard laboratory conditions?

Accepted Answer

1-3 mm/min

Answer

4-6 mm/min

Answer

6-9 mm/min

Answer

10-13 mm/min

Question 10

Which of the following is an acquired condition?

Accepted Answer

Mastitis

Answer

Polymastia (supernumerary breasts)

Answer

Polythelia (extra nipples)

Answer

Amastia (absence of breast tissue)

NEET-PG 2012

Anatomy

Internal Medicine

Physiology

Surgery