The liver is divided into lobes, which divide further into cylindrical lobules. Liver cells are called hepatocytes, have large nuclei and lots of Golgi and mitochondria. Blood from branches of the HPV and hepatic artery are mixed in spaces called sinusoids supplying cells with enough oxygen for their metabolic activity. Kupffer cells in the sinusoids are macrophages that engulf microorganisms and foreign particles and old red blood cells. The blood drains into a branch of the hepatic vein. Hepatocytes secrete bile into canaliculi. This drains into a branch of the bile duct (ductules) which leads to the gall bladder.