The letter x is used to represent the number of chromosomes in a single set:
haploid (one set; 1x)
diploid (two sets; 2x)
triploid (three sets; 3x), for example sterile saffron crocus, or seedless watermelons, also common in the phylum Tardigrada
tetraploid (four sets; 4x), for example Salmonidae fish, the cotton Gossypium hirsutum
pentaploid (five sets; 5x), for example Kenai Birch (Betula kenaica)
hexaploid (six sets; 6x), for example some species of wheat, kiwifruit
heptaploid or septaploid (seven sets; 7x)
octaploid or octoploid, (eight sets; 8x), for example Acipenser (genus of sturgeon fish), dahlias
decaploid (ten sets; 10x), for example certain strawberries
dodecaploid or duodecaploid (twelve sets; 12x), for example the plants Celosia argentea and Spartina anglica  or the amphibian Xenopus ruwenzoriensis. Classification
Autopolyploidy
Autopolyploids are polyploids with multiple chromosome sets derived from a single taxon. Two examples of natural autopolyploids are the piggyback plant, Tolmiea menzisii and the white sturgeon, Acipenser transmontanum. Most instances of autopolyploidy result from the fusion of unreduced (2n) gametes, which results in either triploid (n + 2n = 3n) or tetraploid (2n + 2n = 4n) offspring. Triploid offspring are typically sterile (as in the phenomenon of triploid block), but in some cases they may produce high proportions of unreduced gametes and thus aid the formation of tetraploids. This pathway to tetraploidy is referred to as the triploid bridge. Triploids may also persist through asexual reproduction. In fact, stable autotriploidy in plants is often associated with apomictic mating systems. In agricultural systems, autotriploidy can result in seedlessness, as in watermelons and bananas.
Iron(II) fumarate, also known as ferrous fumarate, is the iron(II) salt of fumaric acid, occurring as a reddish-orange powder, used to supplement iron intake. It has the chemical formula C4H2FeO4. Pure ferrous fumarate has an iron content of 32.87%, therefore one tablet of 300 mg iron fumarate will contain 98.6 mg of iron (548% Daily Value based on 18 mg RDI). Iron supplement
Ferrous fumarate is often taken orally as an iron supplement to treat or prevent iron deficiency anaemia. See also
Iron - Nutrition


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