The rift valley contains the Jordan River and the Dead Sea, which separates Jordan from Israel and the Palestinian Territories. Jordan has a 26 kilometres (16 mi) shoreline on the Gulf of Aqaba in the Red Sea, but is otherwise landlocked.
Antidiuretic hormone binds to receptors on cells in the collecting ducts of the kidney and promotes reabsorption of water back into the circulation. In the absense of antidiuretic hormone, the collecting ducts are virtually impermiable to water, and it flows out as urine.
This helps to control blood pressure. In addition to making hormones, the kidneys also respond to a number of hormones including vitamin D, aldosterone, prostaglandins, cortisol, parathyroid hormone and calcitonin.