Pollen called pores. Colpi, sulci and pores are major features in the identification of classes of pollen. Pollen may be referred to as inaperturate (apertures absent) or aperturate (apertures present). The aperture may have a lid (operculum), hence is described as operculate. However the term inaperturate covers a wide range of morphological types, such as functionally inaperturate (cryptoaperturate) and omniaperturate. Inaperaturate pollen grains often have thin walls, which facilitates pollen tube germination at any position. Terms such as uniaperturate and triaperturate refer to the number of apertures present (one and three respectively). The orientation of furrows (relative to the original tetrad
Tylosis (botany) then dies as its contents are disgorged into the empty space of the dry vessel and highly effective decay-inhibiting substances, notably tannin, are formed and absorbed by the adjacent vessel walls. Tylosis (botany) A tylosis (plural: tyloses) is a bladder-like distension of a parenchyma cell into the lumen of adjacent vessels in wood. Less certainly, the term tylosis is in use to summarise the physiological process and the resulting occlusion in the xylem of woody plants as response to injury or as protection from decay in heartwood. It is a key process in wall one of the Compartmentalization Of Decay