Biology · Ch 14 — Human Nutrition
Liver
Liver
The liver is a dark reddish-brown gland lying just below the diaphragm, occupying the right upper part of the abdominal cavity. It is the largest gland in the body, weighing about 1.2 to 1.5 kg in an adult. The liver has two lobes, each covered by a thin connective-tissue covering called Glisson's capsule. Each lobe is subdivided into many structural and functional units called hepatic lobules, each roughly polygonal in shape; at the junction of adjoining lobules lies a small triangular portal area, carrying a branch each of the hepatic artery, the hepatic portal vein and a bile duct.
Within a lobule, cords of liver (hepatic) cells are arranged radially around a central vein. Between these cords run blood-filled spaces called sinusoids, in which lie phagocytic Kupffer cells that destroy toxic substances, dead or worn-out blood cells, and micro-organisms.
The hepatic cells produce bile juice, which is collected and carried through the bile duct to be stored in a small sac, the gall bladder. The duct of the gall bladder (the cystic duct) joins the hepatic duct to form the common bile duct. Bile emulsifies fats and makes the food alkaline as it passes into the intestine. …
What this figure shows. A duct-system diagram showing the liver above, connected by bile ducts converging into a common hepatic duct; the gall bladder hangs below the liver, its cystic duct joining the common hepatic duct to form the common bile duct; below and to the right, the leaf-shaped pancreas is shown with its pancreatic duct joining the common bile duct to form a shared hepatopancreatic duct, guarded by a hepatopancreatic sphincter, which opens into the duodenum. Note: the source textbook labels this figure 'Fig. 14.3', the same number already used for the alimentary-canal histology figure earlier in the chapter — an apparent duplicate figure-numbering in the original book, pr …