Remember, endocytosis is the process by which the cell engulfs extracellular material and exocytosis is the process by which the animal cell spits out wasteful types of products. Now, let's move on to our Lysosomes. So what exactly is a Lysosome? Well, a Lysosome is a spherically shaped, membrane enclosed organelle that are found in animal cells, although recent evidence shows that they can also be found in plant cells. So basically, Lysosomes, just like vacuums, contain an acidic environment that is created as a result of the integral proteins found inside the phospholipid bilayer of the Lysosomes. So the H ions are pumped from the cytosol into the Lysosome and that creates that low PH, about 4.8 to five PH.