Understanding the Two Main Types of Cells: Prokaryotic and Eukaryotic

Cells are the very small diverse parts of the body that group together and specialize to perform a specific function. Cell theory states that all organisms are composed of cells and cells that can only come from an existing cell. Additionally, all cells have a plasma membrane that encloses all of the genetic material within them. There are two main types of cells, which are classified into two different groups: prokaryotic cells and eukaryotic cells. These different types of cells differ based on how they are organized.

Prokaryotic cells are characterized by the lack of a membrane bound nucleus. They form organisms that are from the domain bacteria and archaea. Additionally, they usually smaller and simpler in their structure then eukaryotic cells are. Since they are simple cells, they are able to reproduce very quickly and effectively.

Bacteria are one type of these prokaryotic cells. Usually, bacteria receives a negative stigma because some of them cause diseases. However, some types of bacteria play positive roles in the environment. For example, some of them are used to manufacture chemicals, drugs, and even food. They have a unique structure in which cytoplasm is surrounded by a plasma membrane and the cell wall. They are similar to eukaryotic cells in that they also have a plasma membrane that is the same. The function of the cell wall is to maintain the shape of the bacteria cell. It also contains DNA, a single coil chromosome that is found in the nucleoid. Additionally, they have ribosomes, which are essential because they are the sites of protein synthesis. Finally, the cells can have different appendages, including flagella, frimbriae, and conjunction pili. The role of the flagella in the cell is to act as a way of transportation. The frimbriae allow the cell to attach to surfaces. The conjunction pili is what is used for DNA transfer.

Eukaryotic cells differ from their prokaryotic counterparts in that they have a nucleus housing DNA. These are more advanced type of cell in they perform different functions. They are extremely small and require a microscope to be seen, just like prokaryotic cells. The reason why both of these cells are so small is that they need to have surface areas that are able for easy entry exit of materials. These small cells have a high surface area to volume ratio. Cells have adapted throughout time in order to better achieve this function.

Source:
Benitz, Bill. Lecture: Biology. September 7, 2009