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

/tet·rad/ (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) .
Fallot's tetrad  tetralogy of Fallot.

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.

tetrad

[tet′rad]
Etymology: Gk, tetra, four
a group of four chromatids of a synapsed pair of homologous chromosomes during the first meiotic prophase of gametogenesis. The group is formed in preparation for the two meiotic divisions in the maturation of gametes. tetradic, 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]

tetrad

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).
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