30. Following are a list of extracellular matrix proteins (Column A) along with their functional characteristics
    (Column B):

    Which one of the following is the correct match?
    (1) A- i; B-iv; C-iii; D-ii (2) A- ii; B-iii; C-iv; D-i
    (3) A-iii; B-iv; C-i; D-ii (4) A- iv; B-i; C-ii; D-iii

The correct match for the extracellular matrix (ECM) proteins in Column A with their functional characteristics in Column B is:

(1) A – i; B – iv; C – iii; D – ii

Here’s the explanation based on common ECM proteins and their known functions:

• A – Collagen (i): Provides tensile strength and structural support in tissues.

• B – Laminin (iv): Functions in cell adhesion, differentiation, and basement membrane organization.

• C – Fibronectin (iii): Involved in cell adhesion and migration; connects cells to collagen.

• D – Elastin (ii): Confers elasticity and resilience to tissues.

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Overview of Extracellular Matrix Proteins and Their Functions

The extracellular matrix (ECM) consists of a network of proteins that support cells and tissues both mechanically and biochemically. The principal ECM proteins contribute distinct properties:

• Collagen: The most abundant ECM protein, collagen provides strength and structural support across many tissues including bone, skin, and cartilage.

• Laminin: Found in the basement membrane, laminin helps organize the matrix and facilitates cell adhesion, differentiation, and migration through interactions with cell surface receptors like integrins.

• Fibronectin: Acts as a linker protein, binding to integrins and bridging cells to the collagen matrix, crucial for cell migration and wound repair.

• Elastin: Provides elasticity, allowing tissues like arteries and lungs to stretch and recoil, thus maintaining functional flexibility.

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Summary Table

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Conclusion

Matching ECM proteins to their functional roles is essential for understanding tissue biology. The correct configuration is (1) A – i; B – iv; C – iii; D – ii, reflecting collagen’s structural role, laminin’s role in cell adhesion and basement membrane assembly, fibronectin’s connective role in adhesion, and elastin’s elasticity contribution.