Organelle Division

Every cell has organelles which function in a similar way to the organs in a human body. Each has their own job and must perform it effectively or risk destruction (cells with problems are targeted for death). This is fine during a cell’s life cycle but when a cell divides, called mitosis, it needs to duplicate itself. We have all seen the picture of a cell dividing over and over again. Most of you would probably also know that the DNA in a cell gets copied and then shipped off into a new cell. Some costs may apply. Most interested readers and even biology students will however skip the next part. What happens to the organelles?

Each organelle is composed of its own phospholipid membrane, just as the cell is, and needs to be in a cell. For each cell to have a set of organelles there needs to be some form of trade. Cells don’t just make organelles from scratch. It would also be highly inefficient. Instead of one cell hogging all the organelles, they share. There are two concepts which relate to this, called organelle biogenesis and organelle inheritance. In organelle biogenesis new organelles are created through a number of methods and when organelles are divided and distributed between the two new cells it is called organelle inheritance. The actual process is a matter of research.

Each organelle has its own process for dividing between two cells in a long, complicated series of steps complete with helper proteins acting in sync to manage every specific task. Thankfully, I’m not talking about that here. We’ll cover two basic processes: stochastic and ordered inheritance. In stochastic inheritance the organelle will duplicate and when the cell divides the new cell will receive some of the duplicates. The mitochondria are an example of this, specifically because there are so many of them in a cell.

In the ordered inheritance a cell will divide through an organelle, such as the endoplasmic reticulum, splitting it into two, unequal pieces which will then be reconstructed by the new cells. Two other possibilities are making new organelles piece by piece or splitting an organelle into pieces and sending some to the new cells. The Golgi apparatus does the latter and can be remade in new cells. New discoveries will further elucidate strategies on organelle biogenesis and aid our understanding of the process while simultaneously giving us keen insight on new treatments for disorders resulting from failures of these processes.