人体是如何消化和吸收的_消化系统

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The digestive tract includes the mouth esophagus stomach

消化道包括口腔、食道、胃

small intestine large intestine rectum and anus

小肠、大肠、直肠、肛门

The pancreas liver and gallbladder are accessory

organs of the digestive tract that have many functions

one of which is to produce digestive juices and enzymes that aid in digestion

其中之一是产生有助于消化的消化液和酶

The digestive tract alters food into readily absorbed nutrients and eliminates waste products

消化道将食物转化为易于吸收的营养物质并消除废物

Digestion begins in the mouth

消化从口腔开始

Saliva moistens the food

唾液会滋润食物

and amylase an enzyme in saliva begins the process of breaking it down

淀粉酶(唾液中的一种酶)开始分解它

Food moves through the esophagus and enters the stomach

食物通过食道进入胃

where digestive enzymes and stomach acid continue breaking it down

消化酶和胃酸继续分解它

The resulting breakdown product called chyme

产生的分解产物称为食糜

contains

包含

carbohydrates

碳水化合物

small proteins

小蛋白质

minerals

矿物质

fats

脂肪

vitamins

维生素

and water

和水

Chyme exits the stomach and enters the small intestine

食糜离开胃并进入小肠

The small intestine digests and absorbs each component of chyme

小肠消化并吸收食糜的各个成分

Pancreatic enzymes eventually break down carbohydrates

胰酶最终分解碳水化合物

into several simple sugars called monosaccharides

分解成几种称为单糖的简单糖

Sodium glucose transporters are responsible for transporting monosaccharides

钠-葡萄糖转运蛋白负责转运单糖

across the intestinal cell membrane into the cell using active transport

使用主动转运穿过肠细胞膜进入细胞

After transport into the cell

转运至细胞后

glucose transporters move the monosaccharides out of the cell

葡萄糖转运蛋白将单糖移出细胞

and eventually into the bloodstream for use by the body

最终进入血液供身体使用

Enzymes called proteases break down proteins into amino acids

称为蛋白酶的酶将蛋白质分解为氨基酸

Like carbohydrates

像碳水化合物

amino acids such as glycine

氨基酸,例如甘氨酸

are co transported with sodium ions

与钠离子共同运输

via the sodium glucose transporter

通过钠-葡萄糖转运蛋白

Various amino acid transporters

各种氨基酸转运蛋白

then transfer amino acids into the interstitial fluid

然后将氨基酸转移到组织液中

where they are available to build proteins needed by the body

它们可以用来构建身体所需的蛋白质

Minerals such as sodium

矿物质,例如钠

are co transported with carbohydrates and amino acids

与碳水化合物和氨基酸共同运输

Liver bile salts emulsify fats

肝胆盐乳化脂肪

Then pancreatic and intestinal enzymes digest them into fatty acids and diglyceride

然后胰腺和肠道酶将它们消化成脂肪酸和甘油二酯

Bile acid droplets called micelles absorb the fatty acids

称为胶束的胆汁酸液滴吸收脂肪酸

and diglyceride as well as any fat soluble vitamins in the chyme

和甘油二酯以及食糜中的任何脂溶性维生素

and deliver them to the intestinal cell wall for absorption

并将它们输送到肠细胞壁吸收

Within the cell

细胞内

the lipids and fat soluble vitamins are packaged into chylomicrons

脂质和脂溶性维生素被包装成乳糜微粒

which are delivered to the lacteals or lymphatic capillaries

被输送到乳糜管或毛细淋巴管

in the intestinal villi

在肠绒毛中

for transport to the lymphatic system and eventual return to the blood

用于运输至淋巴系统并最终返回血液