Small+Intestine+and+Absorption

By: Kimanh Nguyen

The small intestine is an organ in which most chemical digestion takes place.



It involves:


 * 1) Circular folds
 * 2) Villus
 * 3) Villi (plural form of villus)
 * 4) Epithelial cells
 * 5) Capillaries
 * 6) Lymph vessels
 * 7) Vein
 * 8) Artery

Functions/ Structures:

v Circular folds


 * Ø Large valvular flaps extending into the lumen of the bowel
 * Ø Composed of reduplications of the mucous membrane

v Villus/villi


 * Ø Folded surfaces that increases the surface area of the walls of the small intestine
 * Ø Covered with fingerlike projections

v Epithelial cells


 * Ø Composed of tissues that cover the surface of the body and lines internal organs

v Capillaries


 * Ø Smallest blood vessels
 * Ø Brings nutrient and oxygen to the tissues
 * Ø Absorbs carbon dioxide and waste product

v Lymph Vessels


 * Ø Thin walled, valve structures
 * Ø Carry lymph
 * § Lymph: fluid lost by the blood into surrounding tissue

v Vein


 * Ø Blood vessel that returns blood to the heart

v Artery


 * Ø Blood vessel that carries blood from the heart to the tissues of the body