Anatomy
6 questionsWhich of the following statements provides the MOST COMPLETE description of sclerotome function during vertebral development?
Which structure(s) passes behind the inguinal ligament:
Nutrient artery runs ?
Which statement accurately describes a characteristic of synovial joints?
Right ovarian artery is a branch of ?
Ovarian fossa is formed by all except?
NEET-PG 2012 - Anatomy NEET-PG Practice Questions and MCQs
Question 141: Which of the following statements provides the MOST COMPLETE description of sclerotome function during vertebral development?
- A. The notochord forms the nucleus pulposus.
- B. The sclerotome contributes to the formation of vertebral bodies.
- C. The sclerotome surrounds the notochord and the neural tube during development. (Correct Answer)
- D. The sclerotome surrounds the notochord.
Explanation: ***The sclerotome surrounds the notochord and the neural tube during development.*** - The **sclerotome** is the part of the somite that differentiates into mesenchymal cells and migrates to surround both the developing **notochord** (which gives rise to the nucleus pulposus) and the **neural tube** (which forms the spinal cord). - This encirclement is crucial for the formation of the **vertebral column**, providing protection and a structural framework. *The notochord forms the nucleus pulposus.* - While true that the **notochord** contributes to the **nucleus pulposus**, this statement describes the fate of the notochord itself, not the function of the sclerotome. - The question asks for the function of the sclerotome, and this option only details one specific derivative. *The sclerotome contributes to the formation of vertebral bodies.* - This statement is partially true, as the **sclerotome** does indeed form the **vertebral bodies**, arches, and intervertebral discs. - However, it is not the *most complete* description of its function during development, as it omits the crucial aspect of surrounding the neural tube. *The sclerotome surrounds the notochord.* - This statement is correct but **incomplete** as it only mentions the notochord. - The **sclerotome** also surrounds the **neural tube**, which is a vital part of its developmental role in forming the vertebral canal.
Question 142: Which structure(s) passes behind the inguinal ligament:
- A. Femoral branch of genitofemoral nerve
- B. Femoral vein
- C. Psoas major
- D. All of the options (Correct Answer)
Explanation: ***Correct: All of the options*** All three structures pass deep to (behind) the inguinal ligament as they transition from the pelvis/abdomen into the thigh [1]. The inguinal ligament forms the superior border of the femoral triangle [1]. ***Femoral branch of genitofemoral nerve (Correct)*** - Pierces the **psoas major** muscle and descends along its anterior surface - Passes through the **lacuna musculorum** (lateral compartment) deep to the inguinal ligament - Lies **lateral to the femoral artery** - Provides sensory innervation to the skin over the femoral triangle ***Femoral vein (Correct)*** - Continuation of the popliteal vein from the lower limb - Passes through the **lacuna vasorum** (medial compartment/femoral canal) within the **femoral sheath** - Located **medial to the femoral artery** behind the inguinal ligament [1] - Carries deoxygenated blood back to the heart via the external iliac vein ***Psoas major (Correct)*** - Major hip flexor muscle originating from lumbar vertebrae (T12-L5) - Passes through the **lacuna musculorum** deep to the inguinal ligament - Located **lateral to the femoral vessels** - Combines with iliacus to form iliopsoas, inserting on the lesser trochanter of femur
Question 143: Nutrient artery runs ?
- A. Away from epiphysis (Correct Answer)
- B. Towards metaphysis
- C. None of the options
- D. Away from metaphysis
Explanation: ***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.
Question 144: Which statement accurately describes a characteristic of synovial joints?
- A. Hyaline cartilage covers the articular surfaces of synovial joints. (Correct Answer)
- B. The metacarpo-phalangeal joint is a condyloid joint.
- C. Cartilage can sometimes divide the joint into two cavities.
- D. Stability is inversely proportional to mobility in synovial joints.
Explanation: ***Hyaline cartilage covers the articular surfaces of synovial joints.*** - The articular surfaces of bones within a **synovial joint** are covered by a thin layer of **hyaline cartilage**, providing a smooth, low-friction surface for movement [1]. - This **articular cartilage** absorbs shock and protects the underlying bone from wear and tear [1]. - This is a **universal structural characteristic** of all synovial joints, making it the most accurate answer. *The metacarpo-phalangeal joint is a condyloid joint.* - While this statement is factually true (MCP joints are indeed **condyloid/ellipsoid joints** allowing movement in two planes), it describes a **specific type** of synovial joint, not a general characteristic of all synovial joints. - The question asks for a characteristic that describes synovial joints as a category, not an example of one specific joint classification. - This makes it incorrect as the best answer to this question. *Cartilage can sometimes divide the joint into two cavities.* - This statement refers to an **articular disc** or **meniscus**, which is a fibrocartilaginous structure that can partially or completely divide a synovial joint cavity. - This feature is present in **some** synovial joints (like the knee or temporomandibular joint) but is **not universal**. - Since it's not a characteristic of all synovial joints, it's not the best answer. *Stability is inversely proportional to mobility in synovial joints.* - Generally, there is an **inverse relationship** between **stability** and **mobility** in joints; joints designed for great mobility (e.g., shoulder) tend to be less stable, and vice-versa (e.g., hip). - However, this describes a **functional principle** or trade-off rather than a **structural characteristic** that defines synovial joints. - While true, it's not the defining characteristic being asked for in this question.
Question 145: Right ovarian artery is a branch of ?
- A. Abdominal aorta (Correct Answer)
- B. Right internal iliac
- C. Common iliac
- D. External iliac
Explanation: ***Abdominal aorta*** - The **right ovarian artery** typically originates directly from the **abdominal aorta**, just inferior to the renal arteries [1]. - This is a direct branch, supplying blood to the **right ovary**, **fallopian tube**, and surrounding structures [1]. *Right internal iliac* - The **internal iliac artery** primarily supplies the **pelvic organs**, gluteal region, and medial thigh [1]. - While it has branches to pelvic structures, the ovarian artery does not originate from it. *Common iliac* - The **common iliac artery** bifurcates into the **internal and external iliac arteries** at the level of the sacroiliac joint. - It does not directly give off the ovarian artery. *External iliac* - The **external iliac artery** continues as the **femoral artery** below the inguinal ligament, primarily supplying the lower limb. - It does not give off branches to the ovary.
Question 146: Ovarian fossa is formed by all except?
- A. Internal iliac artery
- B. Ureter
- C. Obliterated umbilical artery
- D. Round ligament of ovary (Correct Answer)
Explanation: ***Round ligament of ovary*** - The **round ligament of ovary** (ovarian ligament) connects the ovary to the lateral wall of the uterus and does NOT form any boundary of the ovarian fossa [1]. - It lies medial to the ovary and is not involved in forming the depression of the ovarian fossa [1]. - This ligament anchors the ovary but is separate from the peritoneal boundaries defining the fossa [1]. *Obliterated umbilical artery* - The **obliterated umbilical artery** (medial umbilical ligament) forms the **anterior boundary** of the ovarian fossa [2]. - This is a key anatomical landmark running along the lateral pelvic wall anterior to the ovary [2]. *Internal iliac artery* - The **internal iliac artery** forms the **posterior boundary** of the ovarian fossa [2]. - It lies on the lateral pelvic wall, deep and posterior to the ovarian fossa [2]. - This is one of the main structures defining the fossa's posterior limit [2]. *Ureter* - The **ureter** runs along the lateral pelvic wall and forms part of the **posterior/floor boundary** of the ovarian fossa [2]. - It passes posteroinferior to the ovary, contributing to the fossa's posterior limits [2].
Biochemistry
1 questionsWhat is the classification of the Y chromosome?
NEET-PG 2012 - Biochemistry NEET-PG Practice Questions and MCQs
Question 141: What is the classification of the Y chromosome?
- A. Metacentric
- B. Submetacentric (Correct Answer)
- C. Acrocentric
- D. None of the options
Explanation: ***Submetacentric*** - The **Y chromosome** is classified as submetacentric because its **centromere** is located off-center, resulting in two arms of unequal length. - The short arm (Yp) is smaller than the long arm (Yq), but not as disproportionate as in acrocentric chromosomes. - The **X chromosome** is also submetacentric, making both sex chromosomes belong to this category. *Metacentric* - A **metacentric chromosome** has its **centromere** located in the middle, resulting in two arms of approximately equal length. - Examples include chromosomes 1, 3, 16, 19, and 20, which have nearly equal arm ratios unlike the Y chromosome. *Acrocentric* - An **acrocentric chromosome** has its **centromere** located very close to one end, creating one very short arm and one very long arm. - The five acrocentric human chromosomes are **13, 14, 15, 21, and 22**, which possess satellite DNA and nucleolar organizing regions (NORs) on their short arms. - The **Y chromosome is NOT acrocentric** despite historical confusion; it has a more centrally positioned centromere than true acrocentric chromosomes. *None of the options* - This option is incorrect because the Y chromosome has a specific and well-established classification as **submetacentric** based on its centromere position and arm ratio.
Pathology
1 questionsIn which organ are corpora amylacea typically observed in a pathological context?
NEET-PG 2012 - Pathology NEET-PG Practice Questions and MCQs
Question 141: In which organ are corpora amylacea typically observed in a pathological context?
- A. Thymus
- B. Lymph node
- C. Spleen
- D. Prostate (Correct Answer)
Explanation: ***Prostate*** - **Corpora amylacea**, also known as prostatic concretions, are common, benign findings in the prostate gland, especially with increasing age. - They are composed of glycoproteins and often found within the **acini and ducts of the prostate**. *Thymus* - The thymus is known for **Hassall's corpuscles**, which are epithelial reticular cells arranged concentrically, playing a role in T-cell selection. - **Corpora amylacea** are not typically found in the normal thymus. *Lymph node* - Lymph nodes are characterized by their lymphoid follicles, germinal centers, and medullary cords. - While they can have various inclusions or changes in disease states, **corpora amylacea** are not a typical pathological finding in lymph nodes. *Spleen* - The spleen is primarily involved in filtering blood and immune responses, with distinct red and white pulp regions. - **Corpora amylacea** are not associated with the normal or pathological histology of the spleen.
Physiology
1 questionsHaploid number of chromosomes is first seen in?
NEET-PG 2012 - Physiology NEET-PG Practice Questions and MCQs
Question 141: Haploid number of chromosomes is first seen in?
- A. Spermatogonia
- B. Primary spermatocytes
- C. Secondary spermatocyte (Correct Answer)
- D. Spermatids
Explanation: ***Secondary spermatocyte*** - A secondary spermatocyte is formed after **meiosis I**, where the homologous chromosomes are separated, resulting in a cell with a **haploid number of chromosomes (n)**, although each chromosome still consists of two sister chromatids. - This is the **first stage** where haploidy is achieved in spermatogenesis. - These cells are transient and quickly undergo meiosis II to form spermatids. *Spermatogonia* - Spermatogonia are **diploid (2n)** germline stem cells that undergo mitosis to produce more spermatogonia or differentiate into primary spermatocytes. - They contain the full complement of chromosomes found in somatic cells. *Primary spermatocytes* - Primary spermatocytes are also **diploid (2n)** cells that enter meiosis I. - Before meiosis I, DNA replication occurs, so each chromosome consists of two sister chromatids, but the cell still maintains a diploid chromosome number. *Spermatids* - Spermatids are formed after **meiosis II** from secondary spermatocytes and are also **haploid (n)**. - However, secondary spermatocytes become haploid **earlier** in the process, immediately following the reductional division of meiosis I.
Surgery
1 questionsWhat is the appropriate treatment for an incidentally detected appendicular carcinoid tumor measuring 2.5 cm?
NEET-PG 2012 - Surgery NEET-PG Practice Questions and MCQs
Question 141: What is the appropriate treatment for an incidentally detected appendicular carcinoid tumor measuring 2.5 cm?
- A. Right hemicolectomy (Correct Answer)
- B. Limited resection of the right colon
- C. Total colectomy
- D. Appendicectomy
Explanation: ***Right hemicolectomy*** - An appendiceal carcinoid tumor **larger than 2 cm** (or with **mesoappendix invasion, positive margins, or high-grade features**) warrants a right hemicolectomy due to a significantly higher risk of lymph node metastasis (20-30%). - This 2.5 cm tumor clearly exceeds the 2 cm threshold, making right hemicolectomy the standard of care. - This procedure ensures adequate oncological margins and removal of regional lymph nodes, which is crucial for complete treatment. *Limited resection of the right colon* - This option is insufficient for an appendiceal carcinoid of this size, as it may not remove all regional lymph nodes or provide adequate oncological margins. - Limited resection lacks the systematic lymphadenectomy required for tumors exceeding 2 cm. *Total colectomy* - This is an **overly aggressive** and unnecessary procedure for an isolated appendiceal carcinoid tumor, even one of this size. - Total colectomy is typically reserved for diffuse colonic involvement, multifocal tumors, or specific genetic syndromes, which is not indicated here. *Appendicectomy* - An appendicectomy alone is only appropriate for very small appendiceal carcinoid tumors, typically **less than 1 cm** in size, with negative margins and without evidence of mesoappendix invasion or aggressive features. - For a 2.5 cm tumor, the risk of regional lymph node involvement (20-30%) is too high for appendicectomy to be considered adequate oncological treatment.