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Found Homologous 44 times.

Displaying results 1 to 10.

1. Achiasmatic
Undergoing meiosis , a process where the cell 's nucleus divides, without reaching the stage at which homologous chromatid s pair to exchange genetic material (called chiasma ta).

2. Acrosyndesis
A type of pairing that occurs during meiosis , a process where the cell 's nucleus divides, which involves the terminal portions of homologous chromosomes .

3. Anaphase I
The stage in the first meiotic division of meiosis that follows metaphase I . The pairs of homologous chromosome s are separated from each other and moved to opposite ends of the cell . This stage begins as soon as homologous chromosomes begin separating and ends when the chromosome s arrive at opposite ends of the cell.

4. Balanced translocation
A number of the chromosomal mutations called translocations, where a segment of DNA abnormally becomes attached to the wrong chromosome , which results in two nonhomologous chromosome s being able to cross over , something which normally can occur only between homologous chromosomes.

5. Bivalent (tetrad)
A pair of homologous chromosome s which have joined together (are synaps ed) during prophase I and metaphase I of meiosis .

6. Chiasma (pl. chiasmata)
The point at which homologous chromosome s or chromatid s cross over and exchange genetic material during meiosis , a process in which the cell 's nucleus divides.

7. Chiasma
The site where the exchange of chromosome segments between homologous chromosomes takes place ( crossing-over ) (pl.: chiasmata).

8. Chromosomal mutation
Can refer to any of a number of DNA mutation s which results in a change in the protein encoded by the mutated gene , such as point mutation s, insertion or deletion mutation s ( frameshift mutation s), or nonsense mutation s. More often this refers to mutations involving chromosome s, such as the inversion of part of one chromosome such that the inverted part no longer matches with its homologous pair , a translocation of one part of a chromosome to a different chromosome, deletions of parts of chromosomes, or accidents which happen during the division of the nucleus like the unequal portioning of chromosomes between the daughter cells.

9. Constitutive heterochromatin
Regions on chromosome s which are permanently condensed and genetically inactive in every cell in the body. The condensed portions are always in the same position on both homologous chromosome s. An example is the centromere s. Compare facultative heterochromatin.

10. Cross-hybridization (cross hybridization)
The hydrogen bonding of a single-stranded DNA sequence that is partially but not entirely complementary to a single-stranded substrate . Often, this involves hybridizing a DNA probe for a specific DNA sequence to the homologous sequences of different species .

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