Gallery of Volcanic Rocks. Photo (c) Andrew Alden, licensed to About.com (fair use policy) Igneous rocks -- those which originate from magma -- fall into two categories: Extrusive and intrusive. Extrusive rocks erupt from volcanoes or seafloor fissures, or they freeze at shallow depths. This means that they cool relatively quickly and under low pressures, therefore they are typically fine grained and gassy.
on average it takes the human body approximately two to three hours to excrete a liter of water through the bladder this is dependent on several factors including the absorption of water the components in the water if dehydration is present the time of day and the general health of the person continue reading
Each ureter enters the bladder through a tunnel in the bladder wall, which is angled to prevent the urine from running back into the ureter when the bladder contracts. A ureter is one of two uterine tubes that carry urine from the kidneys to the bladder. Each ureter is about ten to twelve inches long. Urine flows down partly by gravity, but mainly by waves of contractions, which pass several times per minute through the muscle layers of the urethral walls.