Stomach

Stomach is food digestive tract that is wider like bag (kantong). It is located in upper part of stomach cavity to the left, and consist of three parts that is cardiac, fundus, and pylorus.

        Digestive process in stomach happens mechanically and chemically. Mechanical digestion happens when food is stirred (teraduk-aduk) by contracting muscles, while chemical digestion happens in stomach wall that produces enzyme.

        Stomach wall produce mucilage (lendir), gastric acid (asam lambung), pepsin enzyme, and rennin enzyme.

a.   Mucilage

It has function to protect stomach wall from gastric acid.

b.  Gastric acid (HCL)

It has function to kill germ (kuman ) or bacteria that is not resist (tidak tahan) to acid, and it activates pepsinogen to be pepsin.

c.   Pepsin enzyme

It has function to break down (memecah) protein to be peptoned.

d.  Renin enzyme

It has function to coagulate (menggumpalkan) milk protein (casein). This renin enzyme is found in baby.

        The stomach wall consists of muscle that composed circularly, enlengthen, and salnting (menyerong). Contracting gastric muscle causes food is stirred uniformly (merata) with gastric acid

        In the end of stomach is found circular muscle that has function to regulate entering and exiting of food in stomach. The end of stomach that in boundary (berbatasan) with throat has circular muscle that has function to keep food in the stomach, because this muscle is inclined closed (cenderung tertutup) and opened if there is food that enters into stomach or excreted (keluar) when vomiting (muntah). Mainwhile (sedangkan), the end of stomach that is in boundary with small intestine has circular muscle called pylorus circular muscle (otot lingkar pylorus).

        The period of food stored inside stomach depends on the kinds of food. Liquid food is only a moment lies (berada) in stomach compared (dibandingkan) to  dense food (makanan padat) and rich of protein.

        The stomach wall can be hurt by movement of stomach muscle if production of its mucilage is a little amount. That hurt stomach wall will cause stomach is felt bitter if production of gastric acid is excessive (berlebih). The production of gastric acid can increase if we get depression.