Meiosis

meioticsyzygymeiosis Imeiosis IIprophase Imetaphase Ipachytenemetaphase IImeioticallydiakinesis
Meiosis (from Greek μείωσις, meiosis, which means lessening) is a specialized type of cell division that reduces the chromosome number by half, creating four haploid cells, each genetically distinct from the parent cell that gave rise to them.wikipedia
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Behavior mutation

It can occur during meiosis or replication of DNA, as well as due to ionizing or UV radiation, transposons, mutagenic chemicals, viruses and a number of other factors.

Cytogenetics

cytogeneticcytogeneticistchromosomal analysis
Cytogenetics is a branch of genetics that is concerned with how the chromosomes relate to cell behaviour, particularly to their behaviour during mitosis and meiosis.

Nondisjunction

non-disjunctionnondisjunction, geneticdisjunction
There are three forms of nondisjunction: failure of a pair of homologous chromosomes to separate in meiosis I, failure of sister chromatids to separate during meiosis II, and failure of sister chromatids to separate during mitosis.

Eimeria

Once released, the unsporulated oocysts undergo meiosis upon contact with oxygen and moisture.

Polyploidy

tetraploidpolyploidtriploid
Most eukaryotes have diploid somatic cells, but produce haploid gametes (eggs and sperm) by meiosis.

Meiotic recombination checkpoint

The meiotic recombination checkpoint monitors the meiotic recombination during meiosis, and blocks the entry into metaphase I if the recombination is not efficiently processed.

Craticula

In addition to frustule morphology the genus differs from closely related species by its sexual reproduction and movement in response to light.

Genetic linkage

linkagelinkage analysislinked
Genetic linkage is the tendency of DNA sequences that are close together on a chromosome to be inherited together during the meiosis phase of sexual reproduction.

Human genome

genomehuman DNAhuman geneticist
Haploid human genomes, which are contained in germ cells (the egg and sperm gamete cells created in the meiosis phase of sexual reproduction before fertilization creates a zygote) consist of three billion DNA base pairs, while diploid genomes (found in somatic cells) have twice the DNA content.

Barbara McClintock

McClintockBarbara_McClintock_(illustrator)
One of those ideas was the notion of genetic recombination by crossing-over during meiosis—a mechanism by which chromosomes exchange information.

Uniparental disomy

uniparental isodisomydisomyheterodisomy
UPD can be the result of heterodisomy, in which a pair of non-identical chromosomes are inherited from one parent (an earlier stage meiosis I error) or isodisomy, in which a single chromosome from one parent is duplicated (a later stage meiosis II error).

Polysomy

polysomicpolysomic inheritance
Polysomy is usually caused by non-disjunction (the failure of a pair of homologous chromosomes to separate) during meiosis, but may also be due to a translocation mutation (a chromosome abnormality caused by rearrangement of parts between nonhomologous chromosomes).

SMC protein

SMCSMC (structural maintenance of chromosome)SMC (structural maintenance of chromosomes) proteins
For instance, mammals have a meiosis-specific variant of SMC1, known as SMC1β.

YTH protein domain

In molecular biology, the protein domain, YTH refers to a member of the YTH family that has been shown to selectively remove transcripts of meiosis-specific genes expressed in mitotic cells.

Cytokinesis

cytokinescytokineticactin-myosin contractile ring
Cytoplasmic division begins during or after the late stages of nuclear division in mitosis and meiosis.

Kinesin

kinesin IIKIF27kinesin-1
The active movement of kinesins supports several cellular functions including mitosis, meiosis and transport of cellular cargo, such as in axonal transport.

Parasexual cycle

parasexualparasexuality
The parasexual cycle, a process peculiar to fungi and single-celled organisms, is a nonsexual mechanism of parasexuality for transferring genetic material without meiosis or the development of sexual structures.

Genetic memory (biology)

genetic memoryrecipesepigenetic memory
If this memory is recorded in the genetic material and stably inherited through cell division (mitosis or meiosis), it is genetic memory.

Tetrad (meiosis)

tetradtetrad analysisNPD
The tetrad is the four spores produced after meiosis of a yeast or other Ascomycota, Chlamydomonas or other alga, or a plant.

Spindle checkpoint

spindle assembly checkpointbipolar orientationbipolarity
In humans, Down syndrome appears in children carrying in their cells one extra copy of chromosome 21, as a result of a defect in chromosome segregation during meiosis in one of the progenitors. This defect will generate a gamete (spermatozoide or oocyte) with an extra chromosome 21. After fertilisation, this gamete will generate an embryo with three copies of chromosome 21.

Bambusa vulgaris

common bambooB. vulgarisBamboo
Fruits are rare due to low pollen viability caused by irregular meiosis.

Megaspore mother cell

megasporocyte
A megaspore mother cell, or megasporocyte, is a diploid cell in plants in which meiosis will occur, resulting in the production of four haploid megaspores.

Consanguinity

consanguineousblood relativeconsanguine
The degree of relative consanguinity can be illustrated with a consanguinity table in which each level of lineal consanguinity (generation or meiosis) appears as a row, and individuals with a collaterally consanguineous relationship share the same row.