Diuresis used to increase urine output and decrease extracellular fluid volume. Substances in the circulation can also increase the amount of circulating fluid by increasing the osmolarity of the blood. This has the effect of pulling water from the interstitial space, making more water available in the blood and causing the kidney to compensate by removing it as urine. In hypotension, often colloids are used intravenously to increase circulating volume in themselves, but as they exert a certain amount of osmotic pressure, water is therefore also moved, further increasing circulating volume. As blood pressure increases, the kidney removes the excess fluid
Bidder's organ oocytes (egg cells). Only rudimentary oviducts are developed, though, preventing eggs from actually being laid. The Bidder's organ only develops into an ovary analogue when testes are removed experimentally or not functioning properly (e.g. due to exposure to endocrine-disrupting chemicals). Importantly, females can have Bidder's organs in addition to true ovaries, which suggests that the Bidder's organ might not be a rudimentary ovary. It is named in honour of Friedrich Bidder. The organ's internal anatomy consists of two parts; the central portion, consisting of connective tissue and rich in blood vessels, and its periphery, consisting of the cortex, which contains