Tetrad
Encyclopedia
Tetrad may refer to:
- Tetrad (chromosomal pairing), Bivalents or Tetrad of homologous chromosomes consisting of four synapsed chromatids that become visible during the Pachytene stage of meiotic prophase
- Tetrad (pollen formation), group of four haploid and immature pollen grains in tetrahedral fashion produced by meiotic microsporogenesis
- Tetrad (genetics)Tetrad (genetics)The tetrad is the four spores of a yeast or Chlamydomonas, that separate after mating. If the two parents have a mutation in two different genes, the tetrad can segregate as the parental ditype , the non-parental ditype or as the tetratype ....
, the four spores of a yeast - Tetrad (general relativity), a mathematical frame of reference in general relativity
- TetractysTetractysThe tetractys , or tetrad, is a triangular figure consisting of ten points arranged in four rows: one, two, three, and four points in each row...
(or Tetrad), (Greek philosophy) - Tetrad (index notation), a concept in differential geometry
- Tetrad (music)Tetrad (music)A tetrad is a set of four notes in music theory. When these four notes form a tertian chord they are more specifically called a seventh chord, after the diatonic interval from the root of the chord to its fourth note...
, a set of four notes - Tetrad (unit of area)Tetrad (unit of area)A tetrad is an area 2 km x 2 km square. The term has a particular use in connection with the British Ordnance Survey national grid, and then refers to any of the 25 such squares which make up a standard hectad....
, an area 2km x 2km square - TetrominoTetrominoA tetromino is a geometric shape composed of four squares, connected orthogonally. This, like dominoes and pentominoes, is a particular type of polyomino...
, a shape composed of four squares - Tetrad of media effectsTetrad of media effectsGenerally speaking, a tetrad is any set of four things. In Laws of Media and The Global Village , published posthumously, Marshall McLuhan summarized his ideas about media in a concise tetrad of media effects...
, a pedagogical tool