The digestive system is composed mainly of Mouth, Pharynx, Stomach, Liver, Gallbladder, Pancreas, Large Intestine, Small Intestine, Appendix and Rectum. Mouth has mucous membrane lining the inside of the mouth comprises stratified squamous epithelium, termed “oral epithelium”, and an underlying connective tissue termed lamina propria. These tissues are responsible for the production of the fibers as well as the extracellular matrix. Pharynx has a stratified squamous non-keratinized type of epithelium and its function is to provide protection and serve as lining or covering for moist internal cavities of the body. Stomach has a thin simple columnar epithelial layer for secretion and absorption. Liver has a thin capsule of dense connective tissue that binds body parts together. Gallbladder is made up of layers of tissue which are mucosa and lamina propria (loose connective tissue) that makes the skin elastic and helps it to withstand pulling pain. Pancreas composed of exocrine tissue that provide the body a method to release secretions containing proteins, mucus, and other products to epithelial surfaces around the body. Large Intestines have four layers: the mucosa, submucosa, muscular layer, and serosa for absorption and secretion. Small Intestine has mucosa lined by a simple columnar epithelium and its main function is for protection. Appendix has an inner mucosa layer that is responsible for absorption and secretion. And rectum composed of simple columnar epithelium which is responsible for protection.