Renal agenesis. Renal agenesis is a medical condition in which one (unilateral) or both (bilateral) fetal kidneys fail to develop.
Polycrystalline cells are composed of multiple silicon crystals, which is a cheaper way to manufacture solar modules. Put simply, these cells are easier for a factory to produce, so they are less expensive. Polycrystalline cells are made by several methods, but most commonly with a cast of molten silicon.
Polyacrylamide is a polymer (-CH2CHCONH2-) formed from acrylamide subunits, it is long-chain polymer (same molecule repeating itself many times) designed to attract either positively charged particles (organic materials, such as carbon or human waste) or negatively charged particles (inert materials, such as sand or clay).