Today we will focus on mitosis, which is the general division of the nucleus into two genetically identical daughter nucleimi in the cell cycle. This results in two cells that are exact clones of one another. During mitosis, the sister chromatids separate, the nucleus divides, and cytokinesis separates the cytoplasm of the cell, resulting in each new cell containing one copy of DNA from the parent cell. This process occurs when the genetic material is duplicated and then division occurs, producing two identical daughter cells. When the chromosome has duplicated and the two pieces are attached at the centromere, they are referred to as sister chromatids, which are a duplicated chromosome.
Mitosis and Cell Cycle Process Steps
The stages of mitosis include: prophase, metaphase, anaphase, and telophase. In prophase, the chromatin begins to condense, the nucleoli disappear, and chromosomes as identical sister chromatids become visible with a light microscope. Then, the mitotic spindle begins to form. In metaphase, the chromosomes line up in the middle of the cell. Anaphase is when the sister chromatids have separated, and the structures are now referred to as chromosomes. Finally, in telophase, the chromosomes disappear, the nuclear envelope and nucleoli reappear, and the spindle fibers disassemble.
Types of Chromosomal Duplication
There are different types of chromosome duplication disorders, including duplication of chromosome 4, the duplication mutation, and non-sister chromatids. After the chromosomes have been duplicated, there are now 2 sister chromatids which contain identical DNA molecules and are attached by cohesion proteins along their lengths. The region where the sister chromatids appear to be pinched together is called the centromere. During this time, the chromatin of each chromosome is in a long, thin configuration distributed throughout the cell's framework.
Mitosis and Cell Cycle Process Diagram
The cell cycle includes the following main phases: interphase, G₁ (growth 1), S-phase, G₂ (growth 2), and mitosis. During interphase, DNA is duplicated in preparation for cell division. G₁ is when many genes are turned on in order to make proteins necessary to run the metabolism of the cell. In S-phase, DNA is copied while growth and metabolic activity continue, and the DNA is constantly checked for any copying errors. In G₂, cell growth and metabolic activity continue, and the cell prepares for division.
Chromatin and Eukaryotic Cells
The DNA found on each chromosome contains a few hundred to a few thousand genes specifying an organism's traits. The chromosomes of eukaryotic cells are made up of chromatin, which is composed of DNA and associated proteins. This chromatin is involved in the control of gene activity and helps to maintain the structure of the chromosome. Eukaryotes have a characteristic number of chromosomes contained within the nucleus of the cell.
In conclusion, mitosis is an essential process in the cell cycle, involving the duplication and division of genetic material to produce identical daughter cells. This process is crucial for growth, repair, and reproduction in multicellular organisms. Understanding the different stages of mitosis and the types of chromosomal duplication is fundamental in comprehending the complexities of genetic inheritance and cellular function.
