brush border
Quick Summary
The brush border is a specialized structure found on the plasma membrane of certain epithelial cells, most notably in kidney tubules and the small intestine. It is characterized by a dense arrangement of microvilli, which are tiny, finger-like projections.1
The primary function of the brush border, particularly in the small intestine, is to significantly increase the surface area available for absorption. This enhanced surface area is crucial for efficiently absorbing nutrients from digested food and water. The microvilli within the brush border also secrete enzymes that aid in the final stages of digestion, breaking down complex molecules into absorbable units. In kidney tubules, the brush border plays a similar role in reabsorbing essential substances back into the bloodstream.231
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- lactase
It is a so-called brush border enzyme, produced by cells known as enterocytes that line the intestinal walls and form the brush border (a chemical barrier through which food must pass to be absorbed). Mutations in the gene that encodes lactase may result in inherited lactase deficiency, which manifests…
It is a so-called brush border enzyme, produced by cells known as enterocytes that line the intestinal walls and form the brush border (a chemical barrier through which food must pass to be absorbed). Mutations in the gene that encodes lactase may result in inherited lactase deficiency, which manifests…
human digestive systemAbsorption…plasma membrane, known as the brush border, is thicker and richer in proteins and lipids than is the plasma membrane on the epithelial cells at the side and base of the villus. Water and solutes pass through pores in the surface epithelium of the mucosa by active transport and solvent…
…plasma membrane, known as the brush border, is thicker and richer in proteins and lipids than is the plasma membrane on the epithelial cells at the side and base of the villus. Water and solutes pass through pores in the surface epithelium of the mucosa by active transport and solvent…
- human digestive systemVitamin D
…influences the permeability of the brush borders of the enterocytes to calcium.
…influences the permeability of the brush borders of the enterocytes to calcium.