1 Excretion-Wastes such as excess water, salt, urea and uric acid are removed from the body in sweat. 2  Waterproofing-The skin with its oil glands prevents the entry of water into, and loss of water out of the body. 3  Protection from Disease-The intact skin prevents invasion of micro-organisms and dust into the body.ubes called ureters carry waste products from the kidneys to the urinary bladder for storage or for release. Details of the human excretory system. Position and allied structures of the kidneys (top). A cross section of the kidney showing the two major portions (left).
Each leg has a long sciatic nerve that runs through the buttock, down the back of the thigh, and into the foot and toes. Sciatica is pain felt along the course of those nerves and their branches, so while the problem originates in the lower lumbar region of the spine, the symptoms are felt mainly in the legs. Many people with the condition have a history of back problems, but sciatica often starts suddenly. It can be triggered by something minor â even a sneeze.
Sciatica Symptoms, Causes, Treatments. Sciatica pain radiates from the lower back toward the feet. Sciatica may feel like a cramp in the leg, burning, tingling, pins-and-needles or numbness. Learn about sciatica causes, exercises, treatment and pain relief. Read more: Sciatica Symptoms, Causes, Treatments.