What is the difference between mitosis and meiosis? | Mitosis – Simply explained!

What is the difference between mitosis and meiosis?

Both mitosis and meiosis are responsible for nuclear divisions, although both processes differ in their sequence and results. Mitosis is the process by which two identical daughter cells with a double (diploid) set of chromosomes are formed from a mother cell. In contrast to meiosis, only one chromosome division is necessary.Overall, mitosis has the function of distributing the entire genetic information in the form of DNA to two identical cells and is therefore essential for cell reproduction.

In contrast, meiosis is important for the formation of germ cells for sexual reproduction. Since germ cells have a simple (haploid) set of chromosomes, meiosis requires two nuclear divisions. In the first nuclear division, a single set of chromosomes is formed from a double one.

The second equivalent division now separates the sister chromatids from each other, so that we obtain a total of four daughter cells, each with a single set of chromosomes. Thus, mitosis and meiosis differ in the number of divisions, in the number and type of daughter cells and in their duration. The mitosis takes about one hour to complete. Meiosis, on the other hand, takes much longer. The prophase of meiosis alone takes about 24 hours in men (sperm formation) and several years to decades in women (formation and maturation of the egg cell).

What is the interphase?

Interphase is the second part of the cell cycle after mitosis. It always lies between two mitotic divisions and has different tasks. During interphase, the DNA halved in mitosis is doubled again.

In addition, there is general cell growth of the two daughter cells and they are prepared for the renewed mitosis. Just like mitosis, interphase can be divided into several stages. Immediately after mitosis, the G1 phase follows the interphase.

The double chromosome set of the daughter cells consists of only one chromatid each. In this phase the daughter cells grow and many proteins and enzymes are produced. The next phase is the so-called S phase (synthesis phase).

Here the DNA is doubled, so that we still have a double set of chromosomes, but now there are also two chromatids. In the last phase of the interphase, the G2 phase, both daughter cells grow again and prepare for the upcoming mitosis. New mother cells have now developed from the two daughter cells, which can be divided in mitosis.

The interphase lasts on average about 18 hours and thus takes much more time than mitosis (duration about one hour). Important in interphase are two control points that are located at the transition from G1 phase to S phase and from G2 phase to mitosis. Here the cell and especially the genetic information is checked for possible errors.

If an error is found, it is first eliminated before the cell divides. If the error would not be recognized and eliminated, it would propagate through the mitosis more and more into many cells.