Narcissus (plant) corona. Floral tubes can range from long and narrow in sections "Apodanthi" and "Jonquilla" to rudimentary ("N. cavanillesii"). Surrounding the floral tube and corona and reflexed (bent back) from the rest of the perianth are the six spreading tepals or floral leaves, in two whorls which may be distally ascending, reflexed (folded back), or lanceolate. Like many monocotyledons, the perianth is homochlamydeous, that is undifferentiated into separate calyx (sepals) and corolla (petals), but rather has six tepals. The three outer tepal segments may be considered sepals, and the three inner segments petals. The transition point between the floral tube and
Discodermia calyx species, among others with similar toxins, became increasingly studied and important in medicine, particularly relating to chemotherapy. In a later study, scientist concluded that the calyculin A, from "D. calyx," also blocks calcium influx by blocking non-selective ion channels in the cell. Later research looked into "D. calyx" as a species to look at the natural mechanisms that can be used to regulate the toxicity of calyculin A. Scientist found regulation through phosphorylation and dephosphorylation. These among other studies focus on regulation of the toxin as a characteristic of the sponge Discodermia Calyx because of its implications in the fight