What is Cell Division?

Cell division is a process in which cells split for the purpose of growth or reproduction. There are three main types of cell division: binary fission, mitosis, and meiosis.

Binary Fission

Binary fission is a type of cell division that occurs in prokaryotes(archaea and bacteria) and some unicellular eukaryotes(plants, animals, fungi, or protists). It is a form of asexual reproduction in which the genetic information and DNA are replicated, and the copies move to opposite sides of the cell. The cell then splits in half, with each copy of genetic information and DNA in each daughter cell. Both daughter cells are completely identical unless a mutation occurs.

Mitosis

What is Mitosis?

Mitosis is a form of cell division that occurs in most eukaryotes. Mitosis serves the purpose of growth in an organism by creating more cells in the organism. Like binary fission, the cell splits in half. However, the process is more complicated since it occurs in more complicated eukaryotic cells.

Interphase

Interphase is a phase that a cell goes through before the cell division occurs, and is the phase which cells spend most of there life. During this phase, the DNA is copied to get ready for mitosis.

Prophase

This is the first stage of mitosis. During prophase, the chromosomes are doubled and jointed together, forming chromatids. There are the same number of chromatids in a cell as chromosomes in the cell before prophase.

Metaphase

The chromatids line up in the middle of the cell to be split in the next stage. The nuclear membrane dissolves. Microtubules grow from each side of the cell, and attach themselves to chromatid halves.

Anaphase

Microtubules grow shorter, causing the chromatids to be pulled apart into chromosomes. Half of the chromosomes are on one end of the cell, and half of the chromosomes are in another end of the cell.

Telophase

The microtubules disappear, and a cell membrane begins to form in the middle of the cell. This is the beginning of the splitting.

Cytokinesis

The cell splits, forming two identical daughter cells with the regular amount of chromosomes in them. The nuclear membrane is formed in each of the cells.

 

Cell Meiosis

What is Cell Meiosis?

Cell meiosis is a form of cell division used for sexual reproduction. In cell meiosis, the phases of cell mitosis are repeated another time. The second repeat is a little bit different from the first. The chromosomes of the mother and father are mixed in the cell.

Prophase I 

After interphase occurs, the chromosomes form in pairs with chromosomes with genetic information from opposite parent. These types of chromosomes are called homologous chromosomes. The genetic information gets mixed up in the chromosome.

 

Metaphase I

The chromosomes line up in the middle of the cell, and microtubules grow from the sides of the cell and attach themselves to chromosome halves.

Anaphase I

The microtubules grow shorter, causing the chromosomes to be split into separate, sister chromosomes. The sister chromosomes move to opposite ends of the cell.

Telophase I

A cell membrane forms in the middle of the cell.

Cytokinesis 

The cell is split into two daughter cells, each with mixed chromosomes.

 

Prophase II

There are  half as many chromosomes in each daughter cell than normal. The chromosomes are split and joined in each cell to form chromatids.

Metaphase II

The nuclear membrane dissolves. The chromatids line up in the middle of the cells, and microtubules grow from the ends of the cells and attach themselves to chromatid halves.

Anaphase II

The microtubules grow shorter and pull the chromatids apart into separate chromosomes, which move to opposite ends of the cells.

Telophase II

Cell membranes form in between each cell.

Cytokinesis

The cells are split, forming 4 special cells with half as many chromosomes as the parent.

After Cell Meiosis

The 4 special cells are called haploid cells. Many of the cells will eventually mature into sperm and egg gamete cells. The sperm cells will transfer their genetic information into egg cells, which form into a zygote. The zygote is the first cell of the new organism.