How do the daughter cells at the end of mitosis compare to the original cell?
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Living cells go through a series of stages known as the cell cycle. The cells grow, copy their chromosomes, and then divide to form new cells. Show
The period between cell divisions is known as 'interphase'. Cells that are not dividing leave the cell cycle and stay in G0. Mitosis and meiosisCells divide into two different ways to make new cells. MitosisMitosis is used to produce daughter cells that are genetically identical to the parent cells. The cell copies - or 'replicates' - its chromosomes, and then splits the copied chromosomes equally to make sure that each daughter cell has a full set. Your body contains trillions of cells (thousands of millions). But you started life as a single cell - a fertilised egg cell. This cell then divided and divided to make more cells through a process called mitosis. Mitosis is a way of making more cells that are genetically the same as the parent cell. It plays an important part in the development of embryos, and it is important for the growth and development of our bodies as well. Mitosis produces new cells, and replaces cells that are old, lost or damaged. In mitosis a cell divides to form two identical daughter cells. It is important that the daughter cells have a copy of every chromosome, so the process involves copying the chromosomes first and then carefully separating the copies to give each new cell a full set. Before mitosis, the chromosomes are copied. They then coil up, and each chromosome looks like a letter X in the nucleus of the cell. The chromosomes now consist of two sister chromatids. Mitosis separates these chromatids, so that each new cell has a copy of every chromosome. The copied chromosomes consist of two chromatids joined at the centromere. The process of mitosis involves a number of different stages.  MeiosisMeiosis is used to make special cells - sperm cells and egg cells - that have half the normal number of chromosomes. It reduces the number from 23 pairs of chromosomes to 23 single chromosomes. The cell copies its chromosomes, but then separates the 23 pairs to ensure that each daughter cell has only one copy of each chromosome. A second division that divides each daughter cell again to produce four daughter cells. Some simple organisms - such as bacteria - can reproduce by simply dividing into two new individuals. Other organisms, including human beings, reproduce through sexual reproduction. New individuals are formed by the joining together of two special cells: a sperm cell and an egg cell. The cells in our bodies contain 23 pairs of chromosomes - giving us 46 chromosomes in total. Sperm cells and egg cells contain 23 single chromosomes, half the normal number, and are made by a special form of cell division called meiosis. Meiosis separates the pairs of matching (or 'homologous') chromosomes, so that sperm cells and egg cells have only one copy of each. That way, when an egg cell fuses with a sperm cell, the fertilised egg has a full set: that is, two copies of every chromosome. Meiosis involves two cell divisions: Meiosis I and Meiosis II. Meiosis I separates the matching - or 'homologous' - pairs of chromosomes. Meiosis II divides each chromosome into two copies (much like mitosis). In Meiosis I, each daughter cell receives a mix of chromosomes from the two sets in the parent cell. In addition, the chromosomes in each matching pair swap some genetic material before they are parted in a process called crossing over. These processes produce new combinations of genes in the sperm cells and egg cells. Like mitosis, meiosis is a form of eukaryotic cell division. However, these two processes distribute genetic material among the resulting daughter cells in very different ways. Mitosis creates two identical daughter cells that each contain the same number of chromosomes as their parent cell. In contrast, meiosis gives rise to four unique daughter cells, each of which has half the number of chromosomes as the parent cell. Because meiosis creates cells that are destined to become gametes (or reproductive cells), this reduction in chromosome number is critical — without it, the union of two gametes during fertilization would result in offspring with twice the normal number of chromosomes! Apart from this reduction in chromosome number, meiosis differs from mitosis in yet another way. Specifically, meiosis creates new combinations of genetic material in each of the four daughter cells. These new combinations result from the exchange of DNA between paired chromosomes. Such exchange means that the gametes produced through meiosis exhibit an amazing range of genetic variation. Finally, unlike mitosis, meiosis involves two rounds of nuclear division, not just one. Despite this fact, many of the other events of meiosis are similar to those that occur in mitosis. For example, prior to undergoing meiosis, a cell goes through an interphase period in which it grows, replicates its chromosomes, and checks all of its systems to ensure that it is ready to divide. Like mitosis, meiosis also has distinct stages called prophase, metaphase, anaphase, and telophase. A key difference, however, is that during meiosis, each of these phases occurs twice — once during the first round of division, called meiosis I, and again during the second round of division, called meiosis II. How does the original cell compare to the daughter cells that are produced at the end of cytokinesis?The cell now undergoes a process called cytokinesis that divides the cytoplasm of the original cell into two daughter cells. Each daughter cell is haploid and has only one set of chromosomes, or half the total number of chromosomes of the original cell.
How does the original cell compared to the daughter cells that are produced?The dividing of the DNA ensures that both the “old” cell (parent cell) and the “new” cells (daughter cells) have the same genetic makeup and both will be diploid, or containing the same number of chromosomes as the parent cell.
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