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Found Ploidy 12 times.

Displaying results 1 to 10.

1. 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 .

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

3. Endopolyploidy
Many multiple copies of the chromosome s of a cell which has been repeatedly duplicating and dividing them without undergoing cell division afterwards.

4. Euploid (euploidy)
Describes a cell or individual which has the normal total number of chromosome s. Humans normally have 46 chromosomes per cell. Euploidy is the opposite of aneuploidy .

5. Genomic formula
The method used to identify the number of sets of chromosome s within a cell or organism (i.e. its ploidy ). Each set is designated "n" so one set is n is haploid , two sets is 2n is diploid , three sets is 3n is triploid , four sets is 4n is tetraploid, etc. Also, 2n+1 is known as trisomy (i.e. two full sets plus a third copy of one of the chromosomes).

6. Haploidiploidy
Haploidiploidy is a genetic system in which one sex of the species (usually the male) is haploid (has only one set of chromosome s) and develops from egg s which have not been fertilized by sperm , and the other sex (usually the female) is diploid (has two sets of chromosomes) and develops from fertilized eggs. An example species is the honeybee.

7. Hyperploidy (hyperploid)
Describes a cell or organism which has more than the normal total number of chromosome s. For example, humans normally have 46 chromosomes per cell - but if a human individual has 47 or more chromosomes per cell, then that person is hyperploid. Hyperploidy is the opposite of hypoploidy .

8. Hypoploidy (hypoploid)
Describes a cell or organism which has less than the normal total number of chromosome s. For example, humans normally have 46 chromosomes per cell - but if a human individual has 45 or fewer chromosomes per cell, then that person is hypoploid. Hypoploidy is the opposite of hyperploidy .

9. 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).

10. Ploidy
The number of sets of chromosome s within a cell or organism. Each set is designated "n" so one set is n is haploid , two sets is 2n is diploid , three sets is 3n is triploid , four sets is 4n is tetraploid, etc. Also, unspecified multiple sets (but more than two) is polyploidy , and extremely large number of sets may be designated by number (for example 15-ploid for fifteen sets).


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