What is the difference between the cells that result from mitosis and meiosis?
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Your body is made up of trillions of that all originate from just one—a fertilized egg. The massive multiplication of cells after conception is possible thanks to cell division, which occurs when one cell splits into two. Cell division not only enables growth but also replaces damaged or dead cells and makes reproduction possible. There are two kinds of cell division: and . Show
 What’s the Difference? Mitosis produces two genetically identical “daughter” cells from a single “parent” cell, whereas meiosis produces cells that are genetically unique from the parent and contain only half as much . Most cells in the body regularly go through mitosis, but some do so more often than others. For instance, those that line the stomach replace themselves after just a few days because they’re subjected to strong digestive acids. In contrast, liver cells may wait up to a year to replace themselves. There are also a few types that last a lifetime without dividing, such as some nerve cells and cells that make up the lens of the eye. Meiosis occurs only in the production of sperm and egg cells for sexual reproduction. The Phases of Cell Division Before either mitosis or meiosis occurs, cells go through a preparatory process called interphase, where they grow and make a copy of their genetic information. Mitosis has six phases apart from interphase. The first five phases divide the and its genetic information in half, while the final step splits the entire parent cell into two identical daughter cells. The phases of mitosis are:
Meiosis has similar steps to mitosis but with two sets of divisions. The first division results in two cells that each have two sets of chromosomes, like in mitosis. The second division creates four cells that each contain one set of chromosomes, because the genetic information isn’t copied a second time. One unique feature of meiosis, which takes place during the first round of prophase (prophase I), is a process called . DNA is mixed between matching chromosomes from the different parents, increasing the genetic diversity. NIGMS-Funded Cell Division Research Many scientists who are supported by NIGMS study cell division. Some of these researchers are investigating how cells:
This post is a great supplement to . Our bodies may not regenerate like some of the research organisms described in Pathways, but they can heal and replace damaged cells through mitosis—the subject of this post. Cell division cycle, figure from Wikipedia. Cells that stop dividing exit the G1 phase of the cell cycle into a so-called G0 state. Cells reproduce genetically identical copies of themselves by cycles of cell growth and division. The cell cycle diagram on the left shows that a cell division cycle consists of 4 stages:
ChromosomesChromosomes were first named by cytologists viewing dividing cells through a microscope. The modern definition of a chromosome now includes the function of heredity and the chemical composition. A chromosome is a DNA molecule that carries all or part of the hereditary information of an organism. In eukaryotic cells, the DNA is packaged with proteins in the nucleus, and varies in structure and appearance at different parts of the cell cycle. In G1, each chromosome is a single chromatid. In G2, after DNA replication in S phase, as cell enter mitotic prophase, each chromosome consists of a pair of identical sister chromatids, where each chromatid contains a linear DNA molecule that is identical to the joined sister. The sister chromatids are joined at their centromeres, as shown in the image below. A pair of sister chromatids is a single replicated chromosome, a single package of hereditary information. Human karyotype “painted” using fluorescent DNA probes. These mitotic chromosomes each consist of a pair of sister chromatids joined at their centromeres. The images of the homologous chromosome pairs (e.g., 2 copies of chromosome 1) have been lined up next to each other. Image from Bolzer et al., (2005) Three-Dimensional Maps of All Chromosomes in Human Male Fibroblast Nuclei and Prometaphase Rosettes. PLoS Biol 3(5): e157 DOI: 10.1371/journal.pbio.0030157 Ploidy
Here is a simplified diagram illustrating the overall process and products of mitosis: Source: Wikimedia Commons (https://commons.wikimedia.org/wiki/File:MajorEventsInMeiosis_variant_int.svg) Questions or points to ponder or note about the figure above (answers at bottom of page):
This animation below shows the packaging of DNA and condensation of chromosomes as a cell undergoes mitosis. MeiosisThis is a special sequence of 2 cell divisions that produces haploid gametes from diploid germline cells. It starts with a diploid cell that has undergone chromosomal DNA replication: 2N chromosomes, 4X DNA content. Two successive divisions, with no additional DNA replication, results in 4 haploid gametes: 1N chromosomes, 1X DNA content.
The last point appears to be the most difficult for students to grasp. Consider the X and Y chromosomes. They pair in prophase I, and then separate in the first division. The daughter cells of the first meiotic division have either an X or a Y; they don’t have both. Each cell now has only one sex chromosome, like a haploid cell. Meiosis Overview from Wikipedia by Rdbickel And here is a video that walks through the steps of meiosis:
Chromosomes, chromatids, what is the difference and how many chromosomes are there at different times of the cell cycle and after mitosis and meiosis?Chromosomes by definition contain the DNA that makes up the fundamental genome of the cell. In a prokaryote, the genome is usually packaged into one circular chromosome consisting of a circular DNA molecule of a few million base pairs (Mbp). In eukaryotes, the genome is packaged into multiple linear chromosomes, each consisting of a linear DNA molecule of tens or hundreds of Mbp. Chromosomes exist at all different phases of the cell cycle. They condense and become visible to light microscopy in prophase of mitosis or meiosis, and they decondense during interphase, in the form of chromatin (DNA wrapped around nucleosomes, like “beads on a string”). Meiosis Overview from Wikipedia by Rdbickel The video below is geared toward a high school audience, but it does present a helpful way for recognizing how many chromosomes are present in a cell (and thus the ploidy level of that cell). While watching, see if you can recognize why the products of meiosis 1 are haploid cells: What is the difference in result between mitosis and meiosis?What's the Difference? Mitosis produces two genetically identical “daughter” cells from a single “parent” cell, whereas meiosis produces cells that are genetically unique from the parent and contain only half as much DNA. Most cells in the body regularly go through mitosis, but some do so more often than others.
What is the difference between the cells that result from mitosis and the cells that result from meiosis quizlet?The difference is the cells that result in Mitosis it results in two identical diploid cells and the cells that result in Meiosis result in four haploid cells that are unique. Mitosis produces body cells while Meiosis makes sex cells. Mitosis are diploid cells and Meiosis are haploid cells.
Which cells are the result of meiosis and mitosis?The four daughter cells resulting from meiosis are haploid and genetically distinct. The daughter cells resulting from mitosis are diploid and identical to the parent cell.
What are 2 main differences in mitosis and meiosis?Mitosis involves the division of body cells, while meiosis involves the division of sex cells. The division of a cell occurs once in mitosis but twice in meiosis. Two daughter cells are produced after mitosis and cytoplasmic division, while four daughter cells are produced after meiosis.
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