3.1: Introduction
- Page ID
- 132152
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Learning Objectives
- Describe the various steps of the Cell Cycle and Mitosis.
- State the significance of mitosis in maintaining genetic stability.
- Describe the phases of meiosis and the physical occurrences which occur in sex-cells to produce gametes.
- Outline the importance of sexual reproduction to produce genetic variation.
- Compare and contrast mitosis and meiosis.
Cell division is the process by which a parent cell divides into two or more daughter cells. Cell division usually occurs as part of a larger process, called the Cell Cycle, which we will look at in detail in this chapter. In eukaryotes, there are two distinct types of cell division; a vegetative division, whereby each daughter cell is genetically identical to the parent cell (mitosis) and a reproductive cell division, whereby the number of chromosomes in the daughter cells is reduced by half to produce haploid gametes (meiosis). We have already looked at the process of Meiosis in Chapter 1 and Chapter 2, as the events in meiosis tie in strongly with Mendel’s Laws. Here, we will look closely at Mitosis. Cell growth and division is essential to asexual reproduction and the development of multicellular organisms, and the transmission of genetic information is accomplished in the cellular process of mitosis. This process ensures that a cell division occurs, with each daughter cell inheriting identical genetic material, (i.e., exactly one copy of each chromosome present in the parental cell).
Media Attribution
- Figure 3.1.1Cell Proliferation by Drosophila07 (2020), CC BY-SA 4.0, via Wikimedia Commons
Reference
Drosophila01. (2020, July 27). Cell proliferation [digital image]. Wikimedia Commons. commons.wikimedia.org/wiki/File:Cell_proliferation.jpg
Long Description
- Figure 3.1.1 Blue circles (cells) demonstrating the various stages of cell division: A large blue circle is seen dividing into four, then sixteen circles to represent cell division. Next, a small blue circle is shown to become progressively bigger, to exemplify cell growth. And finally, multiple blue circles are used to show both cell growth and cell division occurring at the same time, which is known as cell proliferation. [Back to Figure 3.1.1]