Nerve plexus nerves form the Sacral plexus. It is located on the posterior wall of pelvic cavity (pelvis minor). Nervi of the plexus innervate the perineal region, buttocks and the lower limb. The largest nerve of the human body, the sciatic nerve is the main branch, that give rami to the motor innervation of the muscles of the foot, the leg and the thigh. Common peroneal nerve and its branches innervate some part of the skin of the foot, the peroneal muscles of the leg and the dorsal muscles of the foot. Coccygeal plexus originate from S4, S5, Co1 spinal nerves. It
Human body and about 23 litres of fluid inside cells. The content, acidity and composition of the water inside and outside cells is carefully maintained. The main electrolytes in body water outside cells are sodium and chloride, whereas within cells it is potassium and other phosphates. The body contains trillions of cells, the fundamental unit of life. At maturity, there are roughly 30–37 trillion cells in the body, an estimate arrived at by totalling the cell numbers of all the organs of the body and cell types. The body is also host to about the same number of non-human cells as well