ploidy
Sign in to savethumb|upright|A haploid set that consists of a single complete set of chromosomes (equal to the monoploid set), as shown in the picture above, must belong to a diploid species. If a haploid set consists of two sets, it must be of a tetraploid (four sets) species.
AI overview
Ploidy refers to the number of complete sets of chromosomes an organism has in its cells. Understanding an organism's ploidy matters because it determines whether a haploid set (a single complete chromosome set) represents all of an organism's genetic material or just part of it—for example, whether it comes from a diploid species with two sets or a tetraploid species with four sets.
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Article
27 sectionsContents
- Etymology
- Types of ploidy
- Haploid and monoploid
- Diploid
- Polyploidy
- In bacteria and archaea
- Variable or indefinite ploidy
- Mixoploidy
- Dihaploidy and polyhaploidy
- Euploidy and aneuploidy
- Homoploid
- Zygoidy and azygoidy
- Special cases
- More than one nucleus per cell
- Ancestral ploidy levels
- Haplodiploidy
- Tissue-specific polyploidy
- Cardiac polyploidy
- Hepatic polyploidy
- Adaptive and ecological significance of variation in ploidy
- Less efficient natural selection in diploid compared to haploid tissue
- Glossary of ploidy numbers
- Specific examples
- Notes
- References
- Sources
- External links
thumb|upright|A haploid set that consists of a single complete set of chromosomes (equal to the monoploid set), as shown in the picture above, must belong to a diploid species. If a haploid set consists of two sets, it must be of a tetraploid (four sets) species.
Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Here sets of chromosomes refers to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair—the form in which chromosomes naturally exist. Somatic cells, tissues, and individual organisms can be described according to the number of sets of chromosomes present (the "ploidy level"): monoploid (1 set), diploid (2 sets), triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), etc. The generic term polyploid is often used to describe cells with three or more sets of chromosomes.