The lysosomes contain chemicals that help digest food and worn-out cell parts. These organelles are located in the cytoplasm, a gel-like substance inside the cell membrane.
The lysosome is known as the digestive system of the cell because it contains enzymes that break down carbohydrates, lipids, proteins, RNA and DNA. This organelle contains approximately 50 different enzymes, all of which are acid hydrolases.
Acid hydrolases do not break down polymers unless they are in an acidic environment. The inside of a lysosome has a pH of approximately 5.0, according to the National Biotechnology Information Center. Acid hydrolases are not active inside the cytoplasm because it has a neutral pH of approximately 7.2.
The digestive enzymes found in lysosomes start out as proteins. These proteins are produced by the endoplasmic reticulum before being sent to the Golgi apparatus in a vesicle. The Golgi apparatus turns the proteins into digestive enzymes and pinches off a smaller vesicle called the lysosome.
When nutrients enter the cell, lysosomes release digestive enzymes to break down the nutrients. If the cell isn't getting enough food, lysosomes will digest other organelles so that the cell does not starve. Lysosomes eliminate worn-out organelles from the cell via the process of autophagy. First, the worn-out organelle is enclosed by a membrane, forming a vesicle. Then the lysosome fuses with the vesicle and digests its contents.