Explain structure, digestion and absorption in small intestine.
Answers
The inner wall, or mucosa, of the small intestine is covered in wrinkles or folds called plicae circulares that project microscopic finger-like pieces of tissue called villi, which in turn have finger-like projections known as microvilli.
The function of the plicae circulares, the villi, and the microvilli is to increase the amount of surface area available for the absorption of nutrients.
Answer:
The small intestine is the main organ of the digestive tract. Digestion of carbohydrates, proteins and fats occurs in the small intestine. The small intestine is 6-7 metres long and has a diameter of 3-4 cm. It is the longest part of the digestive tract. The functions of small intestine are mixing and transporting chyme from the stomach, production of enzymes necessary for digestion and absorption of nutrients. The digestive juices from the liver and pancreas convert carbohydrates into simple sugars and fats into fatty acids. Proteins are converted into amino acids. The finger-like projections on the walls of the small intestine, known as villi, are surrounded by blood capillaries. The main function of the villi is to increase the surface area for absorption. The undigested food is passed to the large intestine.