ABC model of flower development well as in the determination of the floral meristem. Therefore, the "AG" mutants are devoid of androecium and gynoecium and they have petals and sepals in their place. In addition, the growth in the centre of the flower is undifferentiated, therefore the petals and sepals grow in repetitive verticils. The "PLENA" ("PLE") gene is present in "A. majus", in place of the "AG" gene, although it is not an ortholog. However, the "FARINELLI" ("FAR") gene is an ortholog, which is specific to the development of the anthers and the maturation of pollen. In "Petunia", "Antirrhinum" and in maize the C
Chytridiomycota production within the lake. It has been suggested that parasitic chytrids have a large effect on lake and pond food webs. Chytrids may also infect plant species; in particular, "Synchytrium endobioticum" is an important potato pathogen. Arguably, the most important ecological function chytrids perform is decomposition. These ubiquitous and cosmopolitan organisms are responsible for decomposition of refractory materials, such as pollen, cellulose, chitin, and keratin. There are also chytrids that live and grow on pollen by attaching threadlike structures, called rhizoids, onto the pollen grains. This mostly occurs during asexual reproduction because the zoospores that become attached to the pollen