tetrad


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Related to tetrad: Tetrad analysis

tetrad

 [tet´rad]
a group of four similar or related entities, as (1) any element or radical having a valence, or combining power, of four; (2) a group of four chromosomal elements formed in the pachytene stage of the first meiotic prophase; (3) a square of cells produced by division into two planes of certain cocci (Sarcina).

tet·rad

(tet'rad),
1. A collection of four things having something in common, such as a deformity with four features, for example, Fallot tetralogy. Synonym(s): tetralogy
2. In chemistry, a quadrivalent element.
3. In heredity, a bivalent chromosome that divides into four chromatids during meiosis.
[G. tetras (tetrad-), the number four]

tetrad

(tĕt′răd′)
n.
1. A group or set of four.
2. A tetravalent atom, radical, or element.
3. Biology
a. A four-part structure that forms during the prophase of meiosis and consists of two homologous chromosomes, each composed of two sister chromatids.
b. A group of four haploid cells, such as spores, formed by meiotic division of one mother cell.

te·trad′ic adj.

tet·rad

(tet'rad)
1. A group of four things having something in common, such as a deformity with four features, e.g., Fallot tetralogy.
Synonym(s): tetralogy.
2. chemistry A quadrivalent element.
3. genetics A bivalent chromosome that divides into four during meiosis.
[G. tetras (tetrad-), the number four]

tetrad

  1. the four homologous CHROMATIDS which associate during prophase (the PACHYTEN stage) and metaphase of MEIOSIS and are involved in CROSSING OVER.
  2. the four haploid cells produced by one complete meiotic division.

tet·rad

(tet'rad)
Collection of four things having something in common, such as a deformity with four features, e.g., tetralogy of Fallot.
[G. tetras (tetrad-), the number four]
References in periodicals archive ?
Therefore, the non-CHARAC ratios and behavior of coherent elements such as Y and Ho can be interpreted by and/or attributed to tetrad effect feature in the geochemical processes (Abedini et al., 2017; Rezaei Azizi et al., 2017; Abedini et al., 2018b).
To investigate the wormhole solutions, we assume a diagonal tetrad [31] as
Here's a dark thought: Do be vigilant about family members and friends showing signs of trolling and the Dark Tetrad. I worry especially about the young, who, seeing all the trolling, might believe that it is acceptable behavior.
The parts of the tetrad have the same complementary character:
The [n.sup.5]dU tetrad was observed having circular double Hbonds and this provided higher stability than T or [br.sup.5]U [49].
McLuhan's tetrad can be a useful tool for making meaning from the apparently chaotic signals.
May 11 ~ May 13###The late uninucleate stage###The megaspore mother cell meiosis to form tetrad
Using the study data we constructed two tetrads--one for the paper and marker media, and another for the tablet as the media in the center of the tetrad. In Laws of Media McLuhan and McLuhan (1988) constructed a tetrad analysing the written word as a medium.
The tetrad is said be some to signal the End of Days, while others believe it signifies a significant religious event.
What makes this celestial show even more unique is that this is fourth and final eclipse in a tetrad. A tetrad is a sequence of four total lunar eclipses that happen six months apart.
It will be the fourth of four total lunar eclipses in a two year period, which is known as a Lunar Tetrad - four total lunar eclipses six months apart.
Monday's eclipse marks the completion of an unusual line-up of four total eclipses at six monthly intervals known as a "tetrad".