BioScience Dictionary

 
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Ot.

Found Chromosomes 76 times.

Displaying results 1 to 10.

1. 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 .

2. 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 .

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. Anaphase
Phase of mitosis in which the chromosomes begin to separate.

5. Aneuploid (aneuploidy)
Describes a cell or organism which has an abnormal total number of chromosome s and where numbers of individual chromosomes are out of proportion with the numbers of the other chromosomes. Too many chromosomes is called hyperploidy ; too few is called hypoploidy . Aneuploidy is the opposite of euploidy .

6. Aneuploidy
Variation in chromosome number involving one or a small number of chromosomes; commonly involves the gain or loss of a single chromosome.

7. Assortment
A way in which meiosis produces new combinations of genetic information. Paternal and maternal chromosomes line up randomly during synapsis , so each daughter cell is likely to receive an assortment of maternal and paternal chromosomes rather than a complete set from either.

8. Autosome
A chromosome not involved in sex determination. The diploid human genome consists of 46 chromosomes, 22 pairs of autosome s, and 1 pair of sex chromosome s (the X and Y chromosomes).

9. Autosomes
The chromosomes other than the sex chromosomes . Each member of an autosome pair (in diploid organisms) is of similar length and in the genes it carries.

10. 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.


View web definitions »

Learn more about Chromosomes »