The Bowman's capsule (other names: capsula glomeruli, glomerular capsule) is a cup-like sac at the beginning of the tubular component of a nephron in the mammalian kiney. A glomerulus is enclosed in the sac. Fluids from blood in the glomerulus are collected in the Bowman's capsule (i.e., glomerular filtrate) and further processed along the nephron to form urine. This process is known as ultrafiltration.