A lysosome is a structure inside an animal cell which breaks down materials into compounds which can be used or discarded by the cell, as needed. Lysosomes also play other important roles in cell upkeep, ranging from consuming worn-out structures within the cell to attacking foreign bacteria before it has a chance to penetrate the cells. With a powerful microscope, it is possible to see lysosomes within the cell; these structures are typically spherical in shape.
These structures are considered to be a form of organelle, meaning that they are a highly specialized structure within a cell. Organelles are responsible for the function of a cell, ensuring that it does what it is supposed to, replicates when it should, and dies off when it is no longer useful. These tiny organisms are quite complex, turning each cell into a microcosm of the human body. When organelles malfunction, the results can be very problematic for the host organism.
Each cell contains a multitude of lysosomes, and each lysosome produces an assortment of digestive enzymes which it uses to break down food and waste material. Because a lysosome needs an acidic environment to function properly, these organelles are encompassed in a membrane to ensure that they stay acidic; to digest things, a lysosome engulfs them, treats them with an appropriate enzyme, and then spits the results of the digestion back out for the cell to use.
Lysosomes eat the food supplied to cells by the body, enable recycling of worn organelles, defend cells from bacterial invaders, and patch the cell membrane, in the event that it is breached. Essentially, lysosomes could be viewed as the recycling centers of the cells, ensuring that everything which passes through a cell is utilized to maximum efficiency while discarding anything which cannot genuinely be used.
Christian de Duve is credited with the discovery of these organelles; he published a paper in 1949 which identified lysosomes and their function. A variety of health conditions can be caused by improper function of lysosomes. For example, the failure to generate certain digestive enzymes can cause health problems, as the body lacks the ability to break some things down. Tay-Sachs Disease is a well known example of a lysosome-related disorder.