MSK MCQ QUESTIONS GOT WRONG

A 45-year-old male presents with severe localized lower back pain radiating down his left leg after lifting a heavy box. Magnetic resonance imaging (MRI) reveals a herniated intervertebral disc. Which of the following predominant collagen types is present in the affected structure responsible for resisting these tensile forces?

• A.

  Type IV collagen

B.

Type II collagen

C. Type I collagen

• D.

  Type III collagen

• Your answer C

  Correct answer

  The intervertebral disc contains fibrocartilage, which is rich in Type I collagen to provide high tensile strength and resist mechanical stress.

A biopsy is taken from the hyaline cartilage of the upper respiratory tract. Microscopic examination demonstrates clusters of two to four chondrocytes located within a single lacuna. Which of the following processes directly accounts for the formation of these cell clusters?

Interstitial growth

Correct answer

Isogenous groups form during interstitial growth, where existing chondrocytes within lacunae undergo mitotic division and synthesize new matrix.

A patient suffers an injury to the articular cartilage of the knee joint. Pathological evaluation notes an extremely poor regenerative capacity in this region compared to other cartilage tissues. The absence of which structure best explains this limited repair potential?

Perichondrium

(Your answer)

Correct answer

Articular cartilage lacks a perichondrium, which normally contains the chondrogenic progenitor cells required for tissue repair and appositional growth

A clinical study investigates the mechanics of joints subjected to heavy compressive loads, such as the pubic symphysis and knee menisci. Microscopic analysis shows chondrocytes arranged in parallel rows flanked by dense collagen bands. Which feature distinguishes this tissue from hyaline cartilage

B.

Absence of perichondrium

(Your answer)

Correct answer

Fibrocartilage completely lacks a perichondrium, whereas most hyaline cartilage structures (except articular cartilage) possess one.

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24-year-old male under orthodontic care undergoes tooth realignment using dental braces. The mechanical force applied by the appliance leads to rapid bone remodeling in the alveolar socket wall, characterized by temporary deposition of non-lamellar bone with randomly oriented collagen fibers. Which of the following features is most characteristic of this specific bone type? A. Abundant Haversian systems

B. Presence of heavy mineralization

C. Low concentration of ground substance

D. Irregular collagen arrangement and lower mineral content

E. Outer circumferential lamellae lined by fibrous perichondrium

• Answer: D. Irregular collagen arrangement and lower mineral content

  
  

• Explanation: Woven bone (immature bone) lacks organized lamellae, features randomly arranged cells/collagen fibers, contains more ground substance, and is not heavily mineralized. It is prominently found in the fetal skeleton and adult alveolar sockets during orthodontic adjustments.

A tissue biopsy from the shaft of a femur reveals specialized cells located on the surface of newly synthesized, unmineralized extracellular matrix called osteoid. Which collagen type forms approximately 90% of the organic matrix secreted by these cells? A. Type I collagen

B. Type II collagen

C. Type III collagen

D. Type IV collagen

E. Type X collagen

• Answer: A. Type I collagen

  
  

• Explanation: Osteoblasts synthesize the unmineralized organic matrix known as osteoid. The organic matrix of bone consists primarily of Type I collagen (~90%) along with non-collagenous proteins. (Type II collagen is characteristic of hyaline/elastic cartilage)

A researcher is studying bone lining layers. She isolates a tissue layer lining the internal marrow cavity and extending as a lining into both Volkmann's and Haversian canals. This layer contains osteoprogenitor cells. Which structure is being described? A. Outer fibrous periosteum

B. Inner cellular periosteum

C. Pericellular matrix

D. Endosteum

E. Territorial matrix

• Answer: D. Endosteum

  
  

• Explanation: The endosteum is a thin connective tissue layer containing progenitor cells that lines the internal marrow cavities of spongy bone and extends into the vascular Haversian and Volkmann's canals

. A histology specimen of mature cancellous (spongy) bone is observed under high power. Which structural feature typical of mature compact bone is notably absent in spongy bone trabeculae? A. Osteocytes inside lacunae

B. Bone marrow spaces

C. Endosteum lining

D. Well-developed Haversian systems (Osteons)

E. Lamellated bone matrix

• Answer: D. Well-developed Haversian systems (Osteons)

  
  

• Explanation: Spongy/trabecular bone has a lamellated matrix, contains osteocytes, bone marrow spaces, and an endosteum lining, but lacks Haversian systems (osteons) typical of compact bone.