- In a tissue,cells are bound together by physical attatchment between cell to cell oe between cell to extra cellular matrix. Following are some of the characterstics of cell junctions:
(A) Aderens junctions are cell-matrix anchoring junctions connecting actin filament in one cell with that of matrix
(B) Desmosomes are cell-matrix anchoring junctions connecting actin filament to extra cellular matrix
(C) gap junctions are channel forming junctions allowing passage of small water soluble molecules from cell to cell.
(D) Tight junctions are occluding junctions,which seal gap between two cells
(E) Hemidesmosomes are cell-matrix anchoring junctions connecting intermediate filament in one cell to extra cellular matrix.
Which of the following combinations of statements is NOT correct?
(1) (A) and (B) (2) (A) and (C)
(3) (C) and (D) (4) (D) and (E)
The combination of statements that is NOT correct is:
(1) (A) and (B)
Explanation:
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(A) Adherens junctions are NOT cell-matrix anchoring junctions connecting actin filaments in one cell with that of matrix.
Instead, adherens junctions are cell-cell anchoring junctions connecting actin filaments of adjacent cells via cadherin proteins. -
(B) Desmosomes are NOT cell-matrix anchoring junctions connecting actin filaments to the extracellular matrix.
Desmosomes are cell-cell anchoring junctions that connect intermediate filaments of adjacent cells to provide mechanical strength. -
(C) Gap junctions are correctly described as channel-forming junctions permitting small water-soluble molecules passage cell-to-cell.
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(D) Tight junctions are correctly described as occluding junctions that seal the gap between two cells, creating a barrier.
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(E) Hemidesmosomes are correctly described as cell-matrix anchoring junctions connecting intermediate filaments in one cell to the extracellular matrix.
Summary Table
| Statement Element | Description | True/False |
|---|---|---|
| A (Adherens) | Cell-cell adhesion via actin filaments | False |
| B (Desmosomes) | Cell-cell adhesion via intermediate filaments | False |
| C (Gap junctions) | Channel-forming, small molecule passage | True |
| D (Tight junctions) | Occluding, sealing between cells | True |
| E (Hemidesmosomes) | Cell-matrix anchoring via intermediate filaments | True |
Conclusion
Statements (A) and (B) are incorrect because they mischaracterize adherens junctions and desmosomes as cell-matrix junctions and incorrectly attribute actin filaments to desmosomal linkage. The other statements accurately describe key junction types in animal tissues
1 Comment
Kajal
November 7, 2025A and B