where is glycogen stored in the human body
Glycogen Glycogen functions as one of two forms of long-term energy reserves, with the other form being triglyceride stores in adipose tissue (i.e., body fat). In humans, glycogen is made and stored primarily in the cells of the liver and skeletal muscle.[2][4] In the liver, glycogen can make up from 5–6% of the organ's fresh weight and the liver of an adult weighing 70 kg can store roughly 100–120 grams of glycogen.[2][5] In skeletal muscle, glycogen is found in a low concentration (1–2% of the muscle mass) and the skeletal muscle of an adult weighing 70 kg can store roughly 400 grams of glycogen.[2] The amount of glycogen stored in the body—particularly within the muscles and liver—mostly depends on physical training, basal metabolic rate, and eating habits. Small amounts of glycogen are also found in other tissues and cells, including the kidneys, red blood cells,[6][7][8] white blood cells,[medical citation needed] and glial cells in the brain.[9] The uterus also stores glycogen during pregnancy to nourish the embryo.[10]
Glycogen As a meal containing carbohydrates or protein is eaten and digested, blood glucose levels rise, and the pancreas secretes insulin. Blood glucose from the portal vein enters liver cells (hepatocytes). Insulin acts on the hepatocytes to stimulate the action of several enzymes, including glycogen synthase. Glucose molecules are added to the chains of glycogen as long as both insulin and glucose remain plentiful. In this postprandial or "fed" state, the liver takes in more glucose from the blood than it releases.
Stomach In classical anatomy, the human stomach is divided into four sections, beginning at the gastric cardia,[6] each of which has different cells and functions.
Small intestine Food from the stomach is allowed into the duodenum through the pylorus by a muscle called the pyloric sphincter.