消化系统的基本生理功能是摄取、转运、消化食物和吸收营养、排泄废物，这些

消化系统的基本生理功能是摄取、转运、消化食物和吸收营养、排泄废物，这些生理的完成有利于整个胃肠道协调的生理活动。食物的消化和吸收，供机体所需的物质和能量，食物中的营养物质除维生素、水和无机盐可以被直接吸收利用外，蛋白质、脂肪和糖类等物质均不能被机体直接吸收利用，需在消化管内被分解为结构简单的小分子物质，才能被吸收利用。食物在消化管内被分解成结构简单、可被吸收的小分子物质的过程就称为消化。这种小分子物质透过消化管黏膜上皮细胞进入血液和淋巴液的过程就是吸收。对于未被吸收的残渣部分，消化道则通过大肠以粪便形式排出体外。
在消化过程中包括物理对食物进行化学分解而言。由消化腺所分泌的各种消化液，将复杂的各种营养物质分解为肠壁可以吸收的简单的化合物，如糖类分解为单糖，蛋白质分解为氨基酸，脂类分解为甘油及脂肪酸。然后这些分解后的营养物质被小肠（主要是空肠）吸收进入体内，进入血液和淋巴液。这种消化过程叫化学性消化。
机械性消化和化学性消化两功能同时进行，共同完成消化过程。

結果 (中文) 3:

The basic physiological functions of the digestive system are ingestion, transport, digestion of food and absorption of nutrients, excretion of waste, these physiological completion of the gastrointestinal tract is conducive to the coordination of physiological activities. The digestion and absorption of food, for the needs of material and energy, food nutrients except vitamin, water and inorganic salt can be absorbed directly by, protein, fat and carbohydrate can be directly absorbed by the body, the digestive tube is decomposed into small molecules with simple structure. To be absorbed by the. The process by which food is broken down into a simple structure that can be absorbed in the digestive tract is called digestion. This process of small molecules through the digestive tract epithelial cells into the blood and lymph fluid is absorbed. For non absorbed residues, the digestive tract is excreted in the form of feces through the large intestine.In the digestion process, including physical decomposition of food. All kinds of digestive juice secreted by the digestive gland, the various nutrients complex is decomposed into simple compounds can be absorbed by the intestinal wall, broken down into simple sugars such as sugar, protein into amino acids, lipids into glycerol and fatty acids. Then the decomposition of nutrients by the intestine (mainly jejunum) absorbed into the blood and lymph. This digestion process is called chemical digestion.Mechanical digestion and chemical digestion two functions simultaneously to complete the digestion process.