chiasma
a cross-shaped structure commonly observed between non-sister chromatids during meiosis; the site of crossing over
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Chiasma
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Chiasmata
An X-shaped crossing formed by the crossing over of homologous chromosomes during meiosis when genetic material is exchanged.
Chiasma
A cross-over between strands of two non-sister chromatids during recombination. The junction where two homologous chromosomes appear to exchange genetic material during recombination.
Chiasma (plural chiasmata) Literally a cross. The point at which a genetic recombination event has occurred, visible as a cross-over in meiotic prophase.
chiasma The site where the exchange of chromosome segments between homologous chromosomes takes place (crossing-over) (pl.: chiasmata). PICTURE
chitin A polysaccharide contained in fungi; also forms part of the hard outer covering of insects.
chiasma pl. chiasmata
(ky-as-muh)
The X-shaped, microscopically visible region representing homologous chromatids that have exchanged genetic material through crossing over during meiosis.
chitin ...
Chiasma (plural chiasmata): The points of physical overlap of nonsister chromatids crossing-over in meiosis.
Optic Chiasma (chiasma opticum; optic commissure)."The optic chiasma is a flattened, somewhat quadrilateral band of fibers, situated at the junction of the floor and anterior wall of the third ventricle.
Optic Chiasma the place where the optic nerves cross to the other side of the brain
(opti = the eye; chiasm = cross)
Organelle the "body parts" within a cell
(organum = an instrument‚ implement‚ engine; -elle = small) ...
optic chiasma
a point under the hypothalamus of the brain where the two optic nerves meet and cross over, so that a stimulus from either eye is interpreted in the optic lobe of the opposite side of the brain.
Chiasma
The term which Janssens (1909) introduced for the nodes (Gk. chiasma; cross) where the individual chromosomes making up each pair remain in contact during the diplotene and diakinetic stages of prophase 1 and during metaphase 1 of meiosis.
Chiasma interference: the more frequent (in the case of negative chiasma interference) or less frequent (in the case of positive interference) occurrence of more than one chiasma in a bivalent segment than expected by chance.
Chiasmata separate. Chromosomes, each with two chromatids, move to separate poles. Each of the daughter cells is now haploid (23 chromosomes), but each chromosome has two chromatids.
Telophase I ...
Chiasmata represent points where earlier (and unseen) nonsister chromatids had swapped sections. The process is called crossing over. It is reciprocal; the segments exchanged by each nonsister chromatid are identical (but may carry different alleles).
chiasma A decussation or X-shaped crossing; the places where pairs of homologous chromatids remain in contact during late prophase to anaphase of the first meiotic division.
Anaphase I: Chiasmata break apart and sister chromatids begin migrating toward opposite poles.
Telophase I: CLEAVAGE FURROW forms beginning the process of CYTOKINESIS (cell division). Resulting daughter cells are HAPLOID (1N).
And it turns out that there are these things called chiasmata, which are actually where strands of the duplicated homologous chromosomes break and recombine with the same strand of the other homolog.
The occurrence of a crossing-over is indicated by a special structure, a chiasma (plural chiasmata) since the recombined inner alleles will align more with others of the same type (e.g. a with a, B with B).
When the chromosomes partially separate in late prophase, the areas where crossing over occurred remain attached and are referred to as Chiasmata (sing. chiasma). They hold the chromosomes together until they separate during anaphase.
The final stage of prophase 1 of meiosis when chiasmata terminalize.
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(Redirected from Anaphase I) Jump to: navigation, search ... The chiasmata remain on the chromosomes until they are severed in Anaphase I. ...
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During meiosis, when homologous chromosomes are paired together, there are points along the chromosomes that make contact with the other pair. This point of contact is deemed the chiasmata, ...
 See also: Crossing, Chromosome, Cells, Chromosomes, Meiosis
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