Pre-lysosomes form de novo in the cytoplasm from a cup-shaped membrane called a phagophore. The edges of the phagophore expand while becoming spherical until they seal, enclosing the engulfed pieces of cytoplasm with whatever might lie inside, and giving rise to a double-membrane vesicle. Farquhar observed these closed vesicles, which are known as autophagosomes. Autophagosomes take up damaged molecules or organelles and carry this cargo to the lysosomes. When de Duve observed autophagosomes, he realized that cells could degrade their own components and named the process "autophagy"