How Do Plant Cells Divide?

Just like animal cells, plant cells undergo division through two processes called mitosis and meiosis. Sex cells or gametes are produced by meiosis, while most cells in the plant divide through mitosis.

Mitosis is divided into four phases: prophase, metaphase, anaphase and telophase. Meiosis, by contrast, takes place in two distinct stages, meiosis I and meiosis II. Each stage has four phases, so that meiosis I is divided into prophase I, metaphase I, anaphase I and telophase I, while meiosis II is divided into prophase II, metaphase II, anaphase II and telophase II.

During both processes, the chromatin fibers of the chromosome become condensed and the chromosomes are lined up along the center of the cell by spindle fibers. The spindle fibers pull the chromosomes apart, so that half of the chromosomes go to one daughter cell and half to the other. A new cell wall forms between the two dividing cells through formation of a cell plate from sacs called vesicles.

Meiosis and mitosis exhibit a number of crucial differences. No DNA replication takes place between meiosis I and meiosis II, so the end effect of meiosis is to create four daughter cells, each of which will have half as many chromosomes as the parent cell. During meiosis I, sections of the paternal and maternal copies of a chromosome can be exchanged to create recombinant chromosomes through a process called homologous recombination. This process increases genetic diversity in the plant's offspring and thus plays an important role in evolution.