What cell's are in the digestive system

THE DIGESTIVE SYSTEM The digestive system consists of the digestive tract and associated glands. The main components of the digestive tract are
the: Oral cavity Esophagus Stomach Small Intestine Large Intestine Rectum and anus The entire digestive tract can be considered as a
hollow tube surrounded by a wall composed of
four main layers: Mucosa Submucosa Muscularis Serosa or Adventitia 1. Mucosa The mucosa consists of : epithelium (lining the lumen) lamina propria (loose connective tissue) muscularis mucosae (thin layer of smooth muscle cells). The epithelial lining of the mucosa forms a selective barrier between the external
environment (lumen) and the body. All the food
products that are digested and absorbed by the
body need to pass through the epithelial lining.
This epithelial lining may contain goblet cells, that secrete mucus for lubrication. Endocrine cells (part of the diffuse endocrine system) are
common in the epithelium and produce
polypeptide hormones, that play a role in the
regulation of the digestive processes. The lamina propria, situated just below the epithelium, consists of loose connective tissue,
with an abundant blood supply. Lymphatic
nodules, lymphocytes and plasma cells, and
macrophages are common in the lamina propria
and form a first line of immunological defense
against bacterial and viral invasion. The muscularis mucosa causes local muscular contractions in the mucosa. 2. Submucosa The submucosa consists of dense connective tissue and Meissner's nerve plexus. 3. Muscularis The muscularis consists of two sub-layers of smooth muscle cells (typically inner circular layer, outer longitudinal layer). These are involved in the peristaltic movements of the
intestine. Between these two muscle layers is Auerbach's (myenteric) nerve plexus . The rhythmic peristaltic contractions of the muscularis
are responsible for propelling and mixing food in
the digestive tract. These movements are mainly