I’m sure most of you will know this from high school, but I thought I’d go over it anyways as you’ll probably get tested on this. I’ll make a section on the molecular biology aspects of bioprocessing if this blog gets popular enough for people to request it, though as molecular biology is much more popular of a subject you can definitely find other bloggers who have much more knowledge about it than I do.
Cell: Textbook definition: The smallest structural and functional unit of any living organism, capable of growth, reproduction, functional activity and changes before death.
There are 2 main types of cells: Prokaryotic cells and Eukaryotic cells. Below is a list of differences between them.
| Prokaryotic Cells | Eukaryotic cells |
| Circular DNA | Linear DNA |
| No organelles, just sub-compartments | Membrane enclosed organelles |
| 70S ribosomes | 80S ribosomes |
| Nucleus absent – naked DNA | Nucleus present |
| Cell division via fission or budding | Cell division via mitosis |
| 1 chromosome | More than 1 chromosome |
| Cell wall, made of peptidoglycans | If there is a cell wall, made of chitin or cellulose |
| Generally smaller | Generally bigger |
Those are probably the most important differences between them. Bacteria are prokaryotes, mammals, plants and fungi are eukaryotes.
Now for organelles: Organelles are basically the organs of the cell. These are only present in eukaryotic cells, except for ribosomes. Prokaryotic cells perform reactions in the cytoplasm and with the external environment. Below is a list of the organelles and functions:
| Nucleus | Contains the DNA |
| Nucleolus | Within the nucleus, where ribosomes are synthesized |
| Ribosomes | Synthesize proteins |
| Mitochondria | Generate ATP i.e energy |
| Rough Endoplasmic reticulum (ER) | Has many associated ribosomes, site of membrane and secretory protein synthesis |
| Smooth ER | Makes lipids |
| Golgi Body | Modifies, packages and sorts proteins |
| Cytosol | Internal fluid of cell – area of cell signalling, protein synthesis, intermediary reactions |
| Cell membrane | Regulates transport of molecules in and out of the cell |
| Lysozymes | Contain digestive proteins |
Bioprocessing Explained 