The ARK (also spelled Ark) is a barrel attachment found in the Extinction maps Awakening and Exodus. It allows weapons to turn into a laser weapon, though it still uses conventional ammunition and also has the additional effect of causing extra damage to cryptids, which further makes any that are killed with the weapon it's attached to explode in a similar fashion as to the Pipe Bombs.
A kidney, ureter, and bladder (KUB) study is an X-ray study that allows your doctor to assess the organs of your urinary and gastrointestinal systems. Doctors can use it to help them diagnose urinary disorders and causes of abdominal pain.
The ureter is the tube through which urine moves from the kidney to the bladder. A diagram of a kidney. The renal tubule is part of the filtration system in the nephrons of the kidneys. The distal convoluted tubule helps regulate the pH of the urine by secreting positively charged protons. The kidney contains 4 million nephrons, which are responsible for filtering the blood.