Welcome to the Cellular Mitosis Interactive Simulator!
Cell division was first discovered by Hugo von Mohl in 1835, as he worked with the green algae named Cladaphora glomerata.
The process of cell division begins with Interphase. This mitotic phase is relatively short compared to the length of interphase. When the cell is in interphase, the cell grows by producing proteins and cytoplasmic organelles.
The next step in the cell cycle is prophase. The cell prepares to divide by tightly condensing its chromosomes, as well as starting mitotic spindle formation. In this stage, the chromosomes are long, thin, and thread-like.
At the beginning of prometaphase, the nuclear envelope, containing all the chromosomes dissolves. Then, the kinetochore microtubules attach themselves to the chromosomal kinetochores. A mitotic spindle is formed by the polar microtubules of one centrosome interacting with the opposite polar microtubules of the other centrosome.
Now the cell has entered metaphase. The two centrosomes begin to pull the chromosomes towards opposite ends of the cell. To ensure an equal distribution of chromosomes, the “metaphase checkpoint,” an internal cell function, guarantees that kinetochores are properly attached to the mitotic spindle and the chromosomes are aligned. If the cell passes the metaphase checkpoint, then the cell proceeds into anaphase.
During anaphase, the bonds between chromatids are severed, forming two identical chromosomes. The kinetochores are shortened, pulling the chromosomes to opposite ends of the cell. The second part of anaphase, known as anaphase B, causes the cell to elongate, as it prepares to divide in half.
Telophase is the second to last step and can be seen as an inverse of prophase and prometaphase. The microtubules lengthen and cause the cell to elongate more. The old nuclear envelope has broken down, and a new nuclear envelope forms around each pair of chromosomes. Once surrounded by the new nuclear envelope, the chromosomes decondense and become thread-like once again.
Cytokinesis is technically not a part of cellular mitosis and is a separate process entirely. During cytokinesis, the cell “pinches” the middle and breaks off into two new cells.