Bacteria are inside of you, but what is inside of them? This lesson discusses the internal structure of bacteria and whether or not they have organelles.
Background on Bacteria
Bacteria represent the first and most basic form of life on our planet. And we are surrounded by them.
Literally. Your body is made up of roughly ten trillion cells, but living on and in you are another one hundred trillion bacteria. That means that you consist of ten times as many bacteria as you do your own cells. But I’m not telling you this to frighten you.
Most of these bacteria cells live in your intestinal tract and help with digestion. Perhaps less helpful, these bacteria also produce the gas that make up our flatulence.
Definition of Bacteria
So, you are here because you want to know whether or not bacteria have organelles. The short answer is, no, they don’t. But the long answer will take a bit more explanation.
Bacteria are cells that do not contain a nucleus or other membrane-bound organelles. Did you catch the phrase ‘membrane-bound’ in that definition? This is generally what we mean when we use the term organelle, which is a cellular structure, enclosed in a lipid membrane, that has a specialized function within a cell. Bacteria do not have membrane-bound organelles, but they do have many other cellular structures that aid with their life processes.
Basic Structure of a Bacteria Cell
The cell envelope consists of three layers, which are, from the inside to out: the cell membrane, the cell wall and, in some species, the capsule.
The layers serve to protect the bacteria, provide structural support and regulate its interactions with the outside environment. The cell membrane is analogous to a skin encasing the internal components of the bacteria, and the cell wall and capsule act as an external skeleton.Perhaps most similar to organelles found in more complex cells are the flagellum and pili. Both are external projections of the cell membrane. The flagellum is a tail-like structure that aids in motion, and the pili, Latin for ‘hair,’ allow bacteria to attach to external surfaces such as other cells, your intestines or rocks.Internally, the bacteria hosts the nucleoid, which is less of a structure and more of an area.
It’s where the cell’s long, single loop of DNA is located. Many bacteria also contain smaller pieces of DNA called plasmids. Plasmids aren’t used in the bacterium’s day-to-day activities.
However, they contain genes that help the cell react in life-or-death situations, such as when it comes into contact with an antibiotic or another potentially harmful species of bacteria.Finally, we come to the ribosomes, which are also found in more complex cells. However, in bacteria, the ribosomes are free-floating in the cytoplasm and are never attached to another membrane-bound structure. The ribosome is a bundle of protein and genetic material, which, just like in your body, is responsible for producing all the proteins the cell needs to live.
So, there you have it. Bacteria are simple cells that do not contain a nucleus or other membrane-bound organelles. However, they do contain other cellular structures that aid with their life processes.
These include the cellular envelope, the flagellum and pili, and ribosomes.The cellular envelope consists of the cell membrane, cell wall and capsule. It serves to protect the bacteria, provide structural support and regulate the bacterium’s interactions with the outside environment. The flagellum is a tail-like structure that aids in movement, and the pili, which resemble tiny hairs, allow the bacteria to attach to external surfaces.
Finally, bacteria have ribosomes, similar to those found in more complex cells. In bacteria, however, the ribosomes are free-floating in the cytoplasm and are never attached to the membrane-bound organelle. Ribosomes are bundles of protein and genetic material that are responsible for producing all the proteins that the cell needs to live.