False-colour scanning electron micrograph (SEM) of a section through the duodenum. The duodenal wall has muscle layers (at far left, brown). Long ridg

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False-colour scanning electron micrograph (SEM) of a section through the duodenum. The duodenal wall has muscle layers (at far left, brown). Long ridge-like villi (blue, folds in the wall) project into the central lumen (at right). Villi greatly increase the absorptive & secretory surface of the duodenum. Digestive and stomach-acid neutralising enzymes are secreted by the duodenum; food is further digested here; this food is then absorbed into the blood through capillaries found in each villus. To aid absorption, villi are more widely distributed in the duodenum than elsewhere in the intestine. Magnification: x100 at 6x7cm size. Magnification: x160 at 4x5 inch size.

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Size: 4306px × 5341px
Photo credit: © PROF. P. MOTTA/DEPT. OF ANATOMY/UNIVERSITY LA SAPIENZA, ROME/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: anatomy, body, digestion, digestive, duodenum, false-coloured, gut, human, intestinal, intestine, small, system, villi, villus