Cell division occurs in every living being in the form of mitotic or meiotic cell division. It has the purpose of renewing the body substance and producing reproductive cells.
What is cell division?
Cell division has the sense of renewal of body substance and production of reproductive cells. There are two types of cell division: mitotic and meiotic. Initially, each cell consists of a double DNA strand, which means that it can divide and form the other half anew. Mitotic cell division happens in the human body in every cell type except reproductive cells. It has the purpose of renewing the body substance. Mitotic cell division splits first the DNA strand, then the nucleus and the cell itself. Organelles are formed anew, the DNA replicates the respective missing partial strand and two new ones are formed from one cell. Meiotic cell division skips the step of replicating half the DNA strand, so these cells contain only half the DNA. In this way, they can fuse with another cell and create a living being with combined DNA of two cells. Meiotic cell division occurs only in reproductive cells, i.e. eggs and sperm. All other division processes are mitotic.
Function and task
Cell division has two core functions in the human body: renewal of body substance and reproduction. Mitotic cell division serves to renew the body substance. In this process, two completely identical new cells are created from one cell. How often a cell divides depends on its type. Some cells divide every few hours, others only every few days or much longer. The new cells that result from mitotic cell division are also used for wound closure or the growth of organs and tissues, which is particularly important in children. Accordingly, cell division is faster in children than in adults, and even much faster in babies than in children. Mitotic cell division is decisive for the growth process, because the faster cells divide, the more body substance is available and the more growth can take place. Meiotic cell division is also important for the production of reproductive cells. The process starts from an ordinary cell of the body, which carries the duplicated set of DNA. However, the divided DNA now no longer replicates the “missing” half, but the cell divides and each new cell contains only half the DNA set. The shape of the new cells also differs, because oocytes and sperm cells have different properties from the cell from which they originate. They themselves do not divide further at first, as they lack the other half of the DNA strand for this. They only get this back through fertilization, after which they can divide again. Through fertilization, however, they no longer correspond to the DNA set of only one parent, but already represent a completely new living being.
Diseases and ailments
Cell division is a highly complex process during which problems can also occur. Outside influences, such as radioactive radiation or the presence of chemical substances, can already negatively affect the splitting of DNA. As a result, it would not be divided properly or would be reassembled incorrectly, which would either cause the affected cells to die or mutate. They can cause diseases such as cancer, because cell division and the function of the degenerated cells in this form is not intended by the body and usually proceeds exponentially fast. A tumor develops, which can be benign or malignant, but in any case represents a serious disease. With increasing age, cell division slows down. This can be seen in aging processes in various places, such as the skin. New skin cells are no longer produced as quickly, and the skin appears less elastic and youthful. Changes in cell division also cause many other aging processes that are normal but can lead to various complaints and problems that require treatment. Errors in cell division in the meiotic form are risky, since this is where reproductive cells are created and the “correctness” of the egg and sperm is crucial for healthy children. If there is an error in the DNA strand of one of these two cells, it is transferred to the child and forms its complete DNA set.More or less severe hereditary diseases develop for which there is no cure, since a healthy DNA strand would be required for this. If the error is too severe, the pregnant woman may suffer an abortion very early within the first weeks. If this does not happen, a child will be born with congenital disease.Misdirected cell division signals could also lead to other serious diseases, according to recent findings, one of which is Parkinson’s disease. Cell division is always a complex process, whether it is the mitotic or meiotic form. The older the human being, the more likely it is that an error in DNA division and replication will occur at some point during everyday cell division. This can lead to the emergence of pathological cells that can trigger a number of disease states.
