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).
References in periodicals archive ?
He points out that tetrads have only occurred a handful of times in the last 2,000 years, and each of the last three was associated with a major religious milestone.
Combining Libra Industries and Tetrad Electronics brings more than 65 years of experience and manufacturing expertise to the table," said Rod Howell, CEO and owner of Libra.
A detailed developmental study at ultrastructural level of Anaxagorea brevipes (Annonaceae) showed that the parietal tapetum reluctantly invades the locule at the early tetrad stage and secretes both orbicules and other globular lipoidal concretions (Gabarayeva, 1995).
In 2012 he returned to join Tetrad Bank as managing director.
Appendix: The tetrad on Instant Replay (omitted from Laws of Media, by Eric and Marshall McLuhan)
The suite of solutions will enable Tetrad Bank to automate banking operations, expand reach through multiple new channels and launch targeted offerings to retail customers.
General relativity can also be expressed as a teleparallel theory, restoring absolute parallelism by replacing the curvature of space with an embedded tetrad field.
McLuhan also believed that the tetrad analysis revealed in Laws of Media could only be done on man-made objects, not on spider webs or natural processes.
ASTM International Committee E18 on Sensory Evaluation is currently developing a proposed new standard on the Tetrad test, ASTM WK32980, Test Methods for Sensory Analysis - Tetrad Test.
The classic tetrad of calor, dolor, rubor, and tumor is truly a cecrad for inflammation, as originally described in the 1st century AD," Ms.
3 A Although mostly complementary blues and oranges, the painting's color scheme is actually a tetrad, including greens and reds.
Many birdwatchers have adopted a tetrad (or several), others are contributing "roving records" while they're at work or walking the dog.