The knee permits the following movements: flexion, extension, as well as slight medial and lateral rotation. Also, the knee has special locking and unlocking mechanisms, related to movement by the femoral condyles on the tibial plateau.
H&E stain. Bile or gall is a dark green to yellowish brown fluid, produced by the liver of most vertebrates, that aids the digestion of lipids in the small intestine. In humans, bile is produced continuously by the liver (liver bile), and stored and concentrated in the gallbladder (gallbladder bile).
Bilirubin is produced during the recycling of red blood cells in the liver. Bile also serves as a carrier for cholesterol to be excreted. Bile is alkaline in nature and it neutralizes excessive stomach acids before the food enters the ileum. Bile is antibacterial in nature and kills bacteria that may be present in food.