Vesicles are fluid filled sacs formed from single membranes.They are used for storage and transport.They may bud off from other membranous organelles called the endoplasmic reticulum and the Golgi apparatus and contain lipids or peptides.Lysosomes are vesicles containing hydrolytic enzymes such as lysozyme. They are responsible for the breakdown of old cells, waste material, old organelles and pathogens ingested by white blood cells in a process called phagocytosis.Programmed cell death or apoptosis is the process by which unwanted cells are removed.Lysosomes are responsible for breaking down the contents of the cells.