All living cells have the same cell structure, which is to say: plasma membrane, cytosol, ribosomes, and at least one chromosome. The plasma membrane is vital to the cell to be able to perform even basic functions. The plasma membrane is made up of fats and proteins (Editorial Board, 2012). The basic function of the plasma membrane is to be able to allow certain molecules to pass in and out of the cell. The fat helps to allow food and waste to pass through the cell, while the protein serves as channels to allow other substances to flow in and out of the cell. Small molecules such as oxygen pass through the cell passively without using up any energy, while larger molecules, such as sugars, the cell must actively allow passage through the membrane; so they use up energy within the cell. Both prokaryotic cells and some eukaryotic cells contain the cell structure flagella. Flagella are little hair like structures that allow the cell to move easier through a fluid environment. The flagella are similar in both prokaryotic and eukaryotic cells in that it’s used for movement in both cases. The difference is when you take into account why the cell chooses to move. Prokaryotic cells, such as bacteria usually live off of other cells, and as such they use their flagella to help them find suitable hosts. Eukaryotic cells with flagella however use it for different means. The only Eukaryotic cells which have flagella are those within animals. In the case of Eukaryotic cells, the reason for transportation is usually to help the cell perform its function, an example would be that animal sperm cells have flagella, which help them move through their liquid environment and reach the egg cell to perform reproduction in animals (Editorial Board, 2012). For plant cells one of the most structures is the chloroplast. Without chloroplast, plant cells would be unable to