The function of tight junctions in epithelial tissue is to increase the surface area;

a. increase the strength and integrity of the tissue layer
b. increase the solute uptake in the tissue
c. increase the selectivity of transport across the tissue layer
d. increase the flow of water across the tissue layer.

Explanation:

Cell junctions are specialized sites where two cells join, cell junctions are of three types:

Anchoring junctions, tight junctions, communicating junctions

Anchoring junctions hold cells together and communicating junctions connect two cells directly, communicating junctions include: gap junctions and plasmodesmata

Tight junctions seal paracellular boundaries of epithelial cells and prevent leakage of ions and diffusion of proteins in membrane

Proteins which form tight junctions are called claudin, occludin

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