Meiosis | Mitosis | ||
Creates: | Sex cells only: Female egg cells or Male sperm cells | Makes everything other than sex cells | |
Definition: | A type of cellular reproduction in which the number of chromosomes are reduced by half through the separation of homologous chromosomes in a diploid cell. | A process of asexual reproduction in which the cell divides in two producing a replica, with an equal number of chromosomes in haploid cell | |
Produces: | four haploid daughter cells | two diploid daughter cells | |
Steps: | The steps of meiosis are Interphase, Prophase I, Metaphase I, Anaphase I, Telophase I, Prophase II, Metaphase II, Anaphase II and Telophase II. | The steps of mitosis are Interphase, Prophase, Metaphase, Anaphase, Telophase and Cytokinesis | |
Discovered by: | Oscar Hertwig | Walther Flemming | |
Type of Reproduction: | Sexual | Asexual | |
Genetically: | Different | identical | |
Cytokenesis: | Occurs in Telophase I & Telohpase II | Occurs in Telophase | |
Number of Divisions: | 2 | 1 | |
Pairing of Homologues: | Yes | No | |
Function: | sexual reproduction | Cellular Reproduction & general growth and repair of the body | |
Chromosome Number: | Reduced by half | Remains the same | |
Karyokenesis: | Occurs in Interphase I | Occurs in Interphase | |
Crossing Over: | Mixing of chromosomes | Does not occur | |
Centromeres Split: | The centromeres do not separate during anaphase I, but during anaphase II | The centromeres split during Anaphase | |
Occurrence of Crossing Over: | Yes | No | |
Occurs in: | Humans, animals, plants, fungi | all organisms | |
Number of Daughter Cells produced: | 4 | 2 |
Mitosisis a type of cellular reproduction where a cell will produce an identical replica of itself with the same number and patterns of genes and chromosomes.
Meiosis, on the other hand, is a special process in cellular division where cells are created containing gene patterns of different types and combinations with 50% of the number of chromosomes of the original cell.
Meiosis is used in sexual reproduction of organisms to combine male and female, through the spermazoa and egg, to create a new, singular biological organism. Mitosis is used by single celled organisms to reproduce, or in the organic growth of tissues, fibers, and mibranes.
Mitosis is a method of reproduction for single celled organisms that reproduce asexually. An identical version of the organism is created through splitting of the cell in two. Meiosis may result in millions of spermazoa and egg cells with unique genetic patterns. The mating of the two cells formed by meiosis results in a unique genetic offspring of the same species. Meiosis is a major factor in evolution, natural selection, and biodiversity. The processes of cellular division shown in mitosis and meiosis are present in all manner of life forms including humans, animals, plants, fungi, and single celled organisms and species. Essentially any cell based organism of which all organic life is based will exhibit some form of mitosis and meiosis for growth and reproduction of the individual and species.
Mitosis: Interphase- Preprophase- Prophase - Prometaphase - Metaphase- Anaphase -Telophase -Cytokinesis.
Meiosis: Prophase - Metaphase - Anaphase - Telophase.
An overview of the process and phases of meiosis
The process of mitosis
Both Meiosis and Mitosis are found in complex organisms which reproduce sexually. Mitosis may be used for human growth, the replenishment of depleted organs and tissues, healing, and sustenance of the body. Identical versions of cells can be created to form tissues through Mitosis. Meiosis is a special process reserved for the creation of the egg and sperm cells. The same patterns may be found in many species of plant and animal cell reproduction.
The importance of mitosis is the maintenance of the chromosomal set; each cell formed receives chromosomes that are alike in composition and equal in number to the chromosomes of the parent cell.
Meiosis is found to occur in Human, animals, plants while Mitosis is found in single-cell species as well.
Meiosis was discovered and described for the first time in sea urchin eggs in 1876, by noted German biologist Oscar Hertwig.
Walther Flemming discovered the process of Mitosis in 1882.
Mitosis as a form of reproduction for single-cell organisms originated with life itself (around 4 billion years ago). Meiosis is thought to have appeared 1.4 billion years ago.
In mitosis, each daughter cell ends up with two complete sets of chromosomes while in meiosis, each daughter cell ends up with one set of chromosomes.
Both mitosis and meiosis are studied by scientists generally by using a microscope to identify and classify chromosomal patterns and relationships within the cell’s structure. An understanding of the way cells synthesize chromosomes for reproduction can be applied in bio-machines and nano-technology. Transplantation of genes and chromosomes through injection and implantation is used to experiment with bio-engineering and cloning. Understanding the process through which cells replicate also has application in medicine and the study of health and disease.
Difference Between Mitosis and Meiosis
• Categorized under Science
Mitosis vs Meiosis
Meiosis and Mitosis describe cell division in eukaryotic cells when the chromosome separates.
In mitosis chromosomes separates and form into two identical sets of daughter nuclei, and it is followed by cytokinesis (division of cytoplasm). Basically, in mitosis the mother cell divides into two daughter cells which are genetically identical to each other and to the parent cell.
Phases of mitosis include:
1. Interface -where cell prepares for cell division and it also includes three other phases such as G1 (growth), S (synthesis), and G2 (second gap)
2. Prophase – formation of centrosomes, condensation of chromatin
3. Prometaphase- degradation of the nuclear membrane, attachment of microtubules to kinetochores
4. Metaphase- alignment of chromosomes at the metaphase plate
5. Early anaphase- shortening of kinetochore microtubules
6. Telophase- de-condensation of chromosomes and surrounded by nuclear membranes, formation of cleavage furrow.
7. Cytokinesis- division of cytoplasm
2. Prophase – formation of centrosomes, condensation of chromatin
3. Prometaphase- degradation of the nuclear membrane, attachment of microtubules to kinetochores
4. Metaphase- alignment of chromosomes at the metaphase plate
5. Early anaphase- shortening of kinetochore microtubules
6. Telophase- de-condensation of chromosomes and surrounded by nuclear membranes, formation of cleavage furrow.
7. Cytokinesis- division of cytoplasm
Meiosis is a reductional cell division where the number of chromosomes is divided into half. Gametes formations occur in animal cell and meiosis is necessary for sexual reproduction which occurs in eukaryotes. Meiosis influence stable sexual reproduction by halving of ploidy or chromosome count. Without meiosis the fertilization would result in zygote with twice the number of the parent.
Phases of meiosis include:
1. Meiosis I – separation of homologous chromosomes and production of two haploid cells (23 chromosomes, N in humans)
2. Prophase I – pairing of homologous chromosome pair and recombination (crossing over) occurs
3. Metaphase I – Homologous pairs move along the metaphase plate, kinetochore microtubules from both centrioles attach to the homologous chromosomes align along an equatorial plane.
4. Anaphase I – shortening of microtubules, pulling of chromosomes toward opposing poles, forming two haploid sets
5. Telophase I – arrival of chromosomes to the poles with each daughter cell containing half the number of chromosomes
6. Meiosis II – second part of the meiotic process with the production of four haploid cells from the two haploid cells
Summary:
Mitosis – separation of chromosomes into two identical sets of daughter cells
Mitosis – separation of chromosomes into two identical sets of daughter cells
Meiosis- reductional cell division and the number of chromosomes is divided into half; it is essential for sexual reproduction, and therefore it occurs in eukaryotes
Both mitosis and meiosis are mechanisms that describe cell division. The difference is particularly noticeable when one looks at the DNA in the cell's nucleus. After mitosis, each of the daughter cells will have exact same DNA strands, while after meiosis each daughter cell will only have half of the DNA strands. (Sometimes the division is not exactly half/half, but that is not important for this answer).
Because meiosis only has half the information that the parent cell had, the cell is (as far as we know) unable to reproduce by itself. The reason for meiosis is for reproduction of a multi-cellular organism as well as genetic diversity due to crossing over. One daughter cell (from the male of the species) will try to find a compatible daughter cell (from the female of the species) and fertilize it. This then becomes and embryo and the specie has successfully reproduced. And this is how you, the reader, came into existence.
Because meiosis only has half the information that the parent cell had, the cell is (as far as we know) unable to reproduce by itself. The reason for meiosis is for reproduction of a multi-cellular organism as well as genetic diversity due to crossing over. One daughter cell (from the male of the species) will try to find a compatible daughter cell (from the female of the species) and fertilize it. This then becomes and embryo and the specie has successfully reproduced. And this is how you, the reader, came into existence.
- Parent cell - full set of chromosomes in both mitosis and meiosis (2n).
- Number of divisions - mitosis 1; meiosis 2.
- Chromosome number of daughter cells - mitosis full set (2n) and meiosis half set (n).
- Crossing over - mitosis no; meiosis yes
- Paired homologues - mitosis no; meiosis yes
- DNA of daughter cells - mitosis identical to parent; meiosis daughter cells different
- Number of DNA replications - mitosis 1; meiosis 2
- Number of daughter cells - mitosis 2; meiosis 4
- Type of cells - mitosis somatic; meiosis sex cells
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