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Learn.Genetics is one of the most-used science websites. Tens of millions of visitors come to our site each year to find the science and health information they’re looking for. If Learn.Genetics is useful to you, please take a moment to donate – even a few dollars from each of our visitors would add up to a significant amount! Your support will help us keep Learn.Genetics free and available to everyone. It will also help us develop new content for you. Getting mitosis and meiosis confused on a biology exam can cost you a lot of points, so it's important to keep these two cellular processes straight. In this guide, we break down mitosis vs meiosis, explain each of the processes, and lay out their similarities and differences so that you’ll be able to easily explain what each process does and how the two differ.
What Is Mitosis? What Is Meiosis?Mitosis and meiosis are both processes of cell division. Organisms are constantly replenishing their cell supply and creating new cells to replace those that are old or damaged, as well as making cells to be used to create new organisms during sexual reproduction. Mitosis is when a cell divides to create two identical daughter cells. Mitosis occurs in somatic cells (all the cells that aren’t sex cells), and it’s a process critical for producing new cells and keeping the organism alive and healthy. Most cells in the human body only last a few days to a few weeks (an exception is brain cells, which typically last your whole life), so your body must constantly be making new cells through mitosis. All cells go through a process of formation, growth, division, and eventual death. During mitosis, the parent cell’s nucleus is split to form two sets of chromosomes for each of the new daughter cells. You can learn more about this process by reading our in-depth guide to mitosis. Meiosis also involves cell division, however, it occurs in far fewer cells in your body. The only cells that go through meiosis are gametes, or sex cells (sperm in men and eggs in women). Meiosis is needed for sexual reproduction, and each cycle of meiosis creates four daughter cells with exactly half the number of chromosomes as the parent cell. During fertilization, two daughter cells (one from each organism reproducing) will combine to create an embryo with a full set of chromosomes.
How Are Mitosis and Meiosis Similar?As you’ll see in the next section, mitosis and meiosis have many differences, but they follow the same general pattern to complete the cell division process. The biggest similarity between the two is that they both produce new cells. While the cells they create have some key differences, the end goal is the creation of daughter cells that can be used to either keep the organism alive (mitosis) or help create a new organism during sexual reproduction (meiosis). Both mitosis and meiosis begin with a single parent cell which eventually splits to form new daughter cells. They also both are preceded by interphase, a period of growth (sometimes lasting up to 90% of the cell’s life) when DNA is synthesized. During cell replication, mitosis and meiosis follow the same phases: prophase, metaphase, anaphase, and telophase (although meiosis goes through each step twice, while mitosis only goes through each step once). Here’s what happens in each phase:
Prophase:
Metaphase:
Anaphase:
Telophase:
Both processes also end with cytokinesis, which is when the cytoplasm of the cell splits when the cell pinches in the middle and eventually separates, forming two new cells.
 From left to right: interphase, prophase, metaphase, anaphase, telophase, cytokinesis
What Is the Difference Between Mitosis and Meiosis?Although mitosis and meiosis follow the same basic steps, they have more differences than similarities. Most of these differences relate back to the fact that, although both are needed for cell replication, mitosis and meiosis have different purposes: mitosis replaces body cells with identical copies, while meiosis creates genetically different sex cells that will be used to create an entirely new organism. Another difference between mitosis and meiosis is that, during mitosis, there is only one cell division, so the cell goes through the steps of prophase, metaphase, anaphase, and telophase once. However, during meiosis there are two cell divisions, and the cell goes through each phase twice (so there’s prophase I, prophase II, etc.). Additionally, because increasing genetic diversity is a goal of meiosis but not mitosis (where all the daughter cells are identical), during prophase in meiosis, a process called recombination/crossing over occurs. This is when non-sister chromatids of homologous pairs exchange genetic material so that the daughter cells are more genetically diverse from each other. Here’s a chart summarizing the key differences for mitosis vs meiosis:
MitosisMeiosisWhere it occursOccurs in all organisms, except virusesOnly occurs in animals, plants, and fungiCells it producesCreates body/somatic cellsCreates germ/sex cellsNumber of cell divisionsOne cell division ( 4 stages total)Two cell divisions (8 stages total)Prophase lengthProphase is shortProphase I is longerRecombination/crossing overNo recombination/crossing over in prophaseRecombination/crossing over of chromosomes during prophase IMetaphaseDuring metaphase, individual chromosomes line up on cell’s equatorDuring metaphase I, pairs of chromosomes line up on cell’s equatorAnaphaseDuring anaphase, sister chromatids move to opposite ends of the cellDuring anaphase I, sister chromatids move together to the same cell pole. During anaphase II, sister chromatids are separated to opposite ends of the cellNumber of cells createdEnd result: two daughter cellsEnd result: four daughter cellsPloidyCreates diploid daughter cellsCreates haploid daughter cellsGeneticsDaughter cells are genetically identicalDaughter cells are genetically different
Summary: Compare and Contrast Mitosis and MeiosisBelow is a mitosis and meiosis Venn Diagram that summarizes all the key mitosis vs meiosis similarities and differences. On the left side of the diagram, you can see the key features of mitosis, on the right are the key features of meiosis, and where the two circles overlap is where their similarities are listed.
What's Next?If you want to better understand what DNA is, you need to know about nucleotides. In our guide to nucleotides, we explain what they are and how they make up DNA. Vacuoles are a key organelle in cells. Learn everything you need to know about vacuoles, as well as why they're so different in plant vs animal cells, by reading our guide to vacuoles. Are you fine with memorizing details, but struggling with grasping larger bio concepts? Follow along as we walk you through the differences between incomplete dominance vs. codominance and homologous vs. analogous structures. If you learn best through examples, you'll also love our break-down of commensalism. What are the most important science classes to take in high school? Check out our guide to learn all the high school classes you should be taking.
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Have friends who also need help with test prep? Share this article! Christine Sarikas About the Author Christine graduated from Michigan State University with degrees in Environmental Biology and Geography and received her Master's from Duke University. In high school she scored in the 99th percentile on the SAT and was named a National Merit Finalist. She has taught English and biology in several countries. What is meiosis 1 and meiosis 2?There are two divisions in meiosis; the first division is meiosis I: the number of cells is doubled but the number of chromosomes is not. This results in 1/2 as many chromosomes per cell. The second division is meiosis II: this division is like mitosis; the number of chromosomes does not get reduced.
What happens during meiosis 1 and meiosis 2 quizlet?In meiosis I, homologous chromosomes separate resulting in a reduction of ploidy. Each daughter cell has only 1 set of chromosomes. Meiosis II, splits the sister chromatids apart.
What are the major events in meiosis 1 and 2?Homologue pairs separate during a first round of cell division, called meiosis I. Sister chromatids separate during a second round, called meiosis II. Since cell division occurs twice during meiosis, one starting cell can produce four gametes (eggs or sperm).
How is mitosis 1 and meiosis 2 different?The main difference between meiosis II and mitosis is that the meiosis II essentially occurs in haploid cells that have gone through meiosis I whereas the mitosis mainly occurs in diploid cells. Moreover, meiosis II occurs in the production of gametes in sexual reproduction while mitosis occurs in asexual reproduction.
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Meiosis 1 and 2 Worksheet answers
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