The iPhone 6s and 6s Plus are made from a 7000 Series aluminum alloy, which is stronger and more durable than the 6000 series used in the previous-generation iPhones. Apple's also updated the devices with stronger glass, made using a dual ion exchange process.
Two important sacral nerves to the functioning of the bladder and bowel are the pudendal nerve and the pelvic splanchnic nerve. Through a series of reflexes and signals the nerves and the bladder and bowel coordinate with the pelvic floor muscles and external urinary and anal sphincters.
At that point, nerves from the bladder send a message to the brain that the bladder is full, and your urge to empty your bladder intensifies. When you urinate, the brain signals the bladder muscles to tighten, squeezing urine out of the bladder. At the same time, the brain signals the sphincter muscles to relax.