The spleen is the largest immune organ of the body, located in the left upper abdomen, accounting for 25% of the total lymphoid tissue of the body, containing a large number of lymphocytes and macrophages, and is the center of cellular immunity and humoral immunity of the body. It is located deep in the posterior lateral costal arch of the left quaternary rib area, opposite to ribs 9-11, with the long axis coinciding with the 10th rib. The diaphragmatic surface is adjacent to the diaphragm and the left costophrenic sinus, with the stomach in front, adjacent to the left kidney and the left adrenal gland in the back, adjacent to the lower end and the colonic splenic groove, with soft reticuloendothelial cells, and the spleen of an adult is about 10cm~12cm in length, 6cm~8cm in width, and 3cm~4cm in thickness, and it weighs 110g~200g, and it is roughly the size of the palm of your hand, weighing 200g or so, and it is "suspended" by a number of ligaments in the upper abdomen. The spleen is "suspended" in the upper abdomen by several ligaments. Under normal conditions, the spleen cannot be touched, but if the edge of the spleen can be touched in the supine or right lateral position, it means that the spleen is enlarged.
The spleen belongs to the reticulo-cutaneous system and is located in the upper left part of the abdominal cavity. It is dark red in color, soft and brittle, and is prone to rupture and hemorrhage when it is subjected to localized violent blows.
The spleen is an important hematopoietic organ during embryonic life and produces lymphocytes and monocytes after birth. Macrophages in the spleen can phagocytose and destroy senescent red blood cells, platelets and degenerated white blood cells. It also engulfs bacteria, protozoa, and foreign bodies in the blood. The spleen has abundant blood sinusoids that can store a certain amount (about 200 ml) of blood. When the organism exercises strenuously or climbs a mountain or loses blood suddenly, the smooth muscle of the spleen contracts and releases blood to replenish the needs of the organism. The lymphocytes in the spleen also make antibodies.
The pancreas pancreas is the body's second largest digestive gland, behind the stomach and running across the back wall of the abdomen, in front of the 1st and 2nd lumbar vertebrae. (Pictured: duodenum and pancreas)
The pancreas is elongated,, soft, grayish-red or light-red in color, and can be divided into three parts: head, body, and tail. The head of the pancreas is dilated on the right side and is encircled by the duodenum, the end of the pancreatic duct penetrates into the wall of the duodenum, meets the common bile duct, and opens into the duodenal papilla.
The pancreas is divided into two parts: exocrine and endocrine glands. The exocrine glands consist of alveoli (gland cells) and ducts. The alveoli secrete pancreatic juice, and the ducts are the channels through which the pancreatic juice is expelled. Pancreatic fluid contains sodium bicarbonate, trypsin, lipase, amylase, and so on. The pancreatic juice flows through all levels of ducts and into the pancreatic duct. The pancreatic duct opens into the duodenum in the same way as the common bile duct***. Pancreatic juice is discharged into the duodenum through the pancreatic duct.
Pancreatic fluid contains a variety of digestive enzymes that have the effect of digesting proteins, fats, and sugars.
The endocrine glands are composed of islets, clusters of cells of different sizes scattered among the exocrine glands. The pancreatic islets secrete a hormone called insulin, which enters the bloodstream and lymph directly and is mainly involved in the regulation of sugar metabolism. Insufficient secretion of insulin can cause diabetes.