Digestion continued Biliary system Biliary System o Liver

Digestion (continued) Biliary system

Biliary System o Liver n n Unique to subphylum Conservative form and function. Largest gland in body Divided into lobes (in human R, L, quadrate and caudate)

Liver o Major functions n n n Detoxification of metabolic waste (deamination of amino acids – urea), drugs, toxins, alcohols Destruction of spent RBCs and reclamation of their constituents (spleen too) Synthesis and secretion of bile (consists of above) Synthesis of lipoproteins, plasma proteins (including albumin and clotting factors) Synthesis and storage of glycogen

Liver o Endocrine and Exocrine components n n n Both are roles of the hepatocytes (liver cells) Exocrine – bile Endocrine – lots of stuff – added to sinusoids of hepatic lobules Plus, noxious conversions added to bile Embryonic function

Biliary system o Gall Bladder n o Storage and [bile] Ductwork

Liver lobule

Few notes on the Pancreas o o o In curve of duodenum Lobulated Gland separated by septa Exocrine Component – digestive enzymes from acini n can’t secrete active form n secretes proenzyme form (inactive enzyme) Enterokinase (duodenal secretion) – activates proenzyme Endocrine Component – Hormones – sugar metabolism n Insulin and Glucagon – decrease and increase blood sugar levels Islets of Langerhanz n secreted into bloodstream n lots of capillaries associated with islets

1. 2. 3. 4. 5. 6. 7. Central lumen Intercalated duct Intralobular ducts Interlobular ducts Pancreatic duct Ampulla of Vater Duodenum