The intestinal epithelial lining rapidly renews every 4 to 5 days. The renewal is facilitated by intestinal stem cells (ISCs) located at the base of the crypt– a gland located at the bottom of each villus. ISCs divide asymmetrically to form new stem cells and progenitor daughter cells. The daughter cells are called transit-amplifying (TA) cells which move upwards along the crypt and either differentiate into absorptive cells– the enterocytes or secretory cells– including the goblet,...

The pancreas, a vital organ within the abdominal cavity, plays dual roles in the digestive and endocrine systems, collaborating with exocrine and endocrine cells to maintain optimal digestion and blood sugar levels.
Exocrine function is carried out by acinar cells, organized into clusters known as acini. These cells contribute to digestion by releasing substantial quantities of enzyme-rich, alkaline digestive juices.
Concurrently, the dispersed clusters of endocrine cells throughout the...

The pancreas, an essential organ in the human body, is a pinkish-gray elongated structure located posterior to the stomach. It extends laterally from the duodenum towards the spleen and is firmly bound to the posterior wall of the abdominal cavity. The organ's surface has a lumpy, lobular texture that gives it a unique appearance.
The broad head of the pancreas lies within the loop formed by the duodenum, while its slender body reaches towards the spleen. The tail of the pancreas is short and...

The small intestine exhibits a unique histological structure that significantly enhances its function in digestion and nutrient absorption. These structures include circular folds, villi, and various specialized cells that collectively facilitate the digestion of food.
The intestinal lining features transverse folds called circular folds, each housing fingerlike projections known as intestinal villi. These villi are covered by a layer of simple columnar epithelium, also referred to as...

Stem cells are undifferentiated cells that divide and produce more stem cells or progenitor cells that differentiate into mature, specialized cell types. All the cells in the body are generated from stem cells in the early embryo, but small populations of stem cells are also present in many adult tissues including the bone marrow, brain, skin, and gut. These adult stem cells typically produce the various cell types found in that tissue—to replace cells that are damaged or to continuously renew...

Erythropoietin-producing hepatocellular carcinoma receptor (Eph) and its ligand, Eph receptor-interacting protein (Ephrin) were first discovered in the human carcinoma cell line, hence the name. Ephrin-Eph interaction guides cells to reach their appropriate location in adult tissues. They also play an essential role in the immune system by helping in immune cell migration, adhesion, and activation. Based on their structure and function, Eph is divided into two classes — EphA and EphB.