Prophase is one of the first phases of mitosis and it focuses on preparing the spindles, metaphase plate and chromosomes to work in the later phases of the process. Prophase exists in both mitosis and meiosis.Know More
During mitosis and meiosis, prophase is the first phase of the division cycle after DNA replication in G and S phases. The main value of prophase is that the chromatin condenses to become chromosomes, which will later be separated in various ways during the final stages of mitosis and meiosis. The nucleolus in the nucleus also disappears and the cell membrane disappears, which makes it easy for the cell to start to divide into two. The miotic spindles on both sides of the cell, which is made of microtubules, is formed during prophase and gets ready to move. This is an important part of the division, as it pulls the chromosomes apart to their respective side.
In both meiosis and mitosis, prophase plays the same role; there are no differences between the three instances, except for the fact that meiosis is only with sex cells (gametes) and mitosis is with regular somatic cells. In meiosis, prophase happens twice because there are two divisions that result in four total cells.Learn more about Cells
The four phases of mitosis are prophase, metaphase, anaphase and telophase. Each stage has its own process.Full Answer >
Crossing over begins very early in the prophase I stage of meiosis. During prophase I, pairs of homologous chromosomes exchange lengths of their genetic material. Crossing over leads to recombinant chromosomes and is a key factor in genetic recombination. This produces genotypes in offspring that are new and different combinations of the parental alleles. Crossing over, along with independent assortment, is the basis for Gregor Mendel’s laws of genetics.Full Answer >
The major difference between prophase I and prophase II is the genetic recombination process that occurs during prophase I, but does not repeat in prophase II. During prophase I, the duplicated homologous pairs line up and cross over, which is the process by which the chromatids exchange genetic information. Because this process occurs during prophase I, it does not need to repeat during prophase II.Full Answer >
Chromosomes first become visible during prophase in mitosis, and they are fully visible during metaphase and anaphase. They lose their visibility during telophase and are not visible during cytokinesis, which follows mitosis.Full Answer >