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Found Chromosome 249 times.

Displaying results 1 to 10.

1. Acentric
This term refers to a chromosome or chromatid that lacks a centromere ; this condition can result during crossing over in which the normal, centromere-containing segment is replaced by an inverted segment that lacks a centromere.

2. Acrocentric
A chromosome or chromatids with a non-centrally-located centromere , producing chromosome arms with unequal lengths.

3. Acrocentric
An acrocentric chromosome has its centromere closer to one end than to the other, resulting in unequal chromosome arms.

4. 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 .

5. Allopolyploid
A hybrid , usually a plant, which is created from two closely-related species and contains one or more extra sets of chromosome s (i.e. if each parent normally has two sets, the hybrid may have four). See polyploid .

6. Allotetraploid hybrid (amphidiploid)
A hybrid , usually a plant, of two different species which has two sets of chromosomes from each of the parent species. Also see allopolyploid .

7. Ameiosis
A form of nuclear division which does not reduce the number of chromosome s because both of the nuclear divisions normally part of the process of meiosis have failed to occur.

8. Anaphase
The stage in mitosis following metaphase . The paired chromatid s are separated from each other and moved to opposite ends of the cell . The stage begins as soon as the centromere s connecting each chromatid to its pair break and ends when the two new sets of chromosome s arrive at opposite ends of the cell.

9. 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.

10. Anaphase II
The stage in the second meiotic division of meiosis that follows metaphase II . In each cell produced during the first meiotic division , the paired chromatid s are separated from each other and moved to opposite ends of the cell. The stage begins as soon as the centromere s connecting each chromatid to its pair break and ends when the two new sets of chromosome s arrive at opposite ends of each cell.


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