The stomach is composed of four layers. Starting from the inside and working our way out, the innermost layer is called the mucosa. Stomach acid and digestive juices are made in the mucosa layer. The next layer is called the submucosa. The submucosa is surrounded by the muscularis, a layer of muscle that moves and mixes the stomach contents. The next layers, the serosa, is the wrapping for the stomach. The serosa is the outermost layer of the stomach. | The stomach is composed of four layers. Starting from the inside and working our way out, the innermost layer is called the mucosa. Stomach acid and digestive juices are made in the mucosa layer. The next layer is called the submucosa. The submucosa is surrounded by the muscularis, a layer of muscle that moves and mixes the stomach contents. The next layers, the serosa, is the wrapping for the stomach. The serosa is the outermost layer of the stomach. |