BioScience Dictionary

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Found Homologous chromosomes 9 times.

Displaying results 1 to 10.

1. 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.

2. 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.

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

4. Diploid
Cells that contain homologous chromosomes . The number of chromosomes in the cells is the diploid number and is equal to 2n (n is the number of homologous pairs).

5. Homologous chromosomes
A pair of chromosome s containing the same linear gene sequence s, each derived from one parent.

6. Homologues
A pair of chromosomes in which one member of the pair is obtained from the organism's maternal parent and the other from the paternal parent; found in diploid cells. Also commonly referred to as homologous chromosomes.

7. Meiosis
Cell division in which the chromosomes replicate, followed by two nuclear divisions. Each of the resulting gametes (in animals, spores in plants) receives a haploid set of chromosomes. Reduction/division by which ploidy, the number of sets of homologous chromosomes , is reduced in the formation of haploid cells that become gametes (or gametophytes in plants).

8. Metaphase I
The stage in the first meiotic division of meiosis that follows prophase I . Homologous chromosome s pair with each other to form tetrad s of four chromatid s and they align themselves along a single plane in the center of the cell . Homologous recombination generally occurs during this stage. This stage ends as soon as the homologous chromosomes start being pulled away from each other, to opposite ends of the cell.

9. Tetrad
The four chromatids in each cluster during synapsis ; formed by the two sister chromatids in each of the two homologous chromosomes .