13) imply that pollen in the common ancestor of Canrightia and Chloranthaceae was globose and monosulcate, with a reticulate-columellar
exine, smooth muri, and a sculptured sulcus membrane, as in Canrightia and Zlatkocarpus, all features inherited from lower in the tree (Doyle, 2005).
Yang, "RUPTURED POLLEN GRAIN1, a member of the MtN3/saliva gene family, is crucial for
exine pattern formation and cell integrity of microspores in Arabidopsis," Plant Physiology, vol.
Regarding to figure 4, (a) shows an oval homogeneous morphology without fissures, while (b) differs in being circular and having three wade edges in the primary wall, although in these morphologies is evident a well-defined structure where
exine is highlighted.
The apocolpium (t) of Cornus mas's pollen grains ranges from 3.97 to 5.85 [micro]m and their
exine thickness (Ex) ranges from 0.99 to 1.77 [micro]m.
Description:Pollen grain, monocolpate, amb oblong to oval elliptical, extremities rounded or blunt, colpus distinct, extending full length of grain, colpus broad in middle with sharp ends, usually marked by parallel, exinal folds on sides, folds Plano convex or biconcave in some cases additional intexinal folds may accompany the major folds,
exine laevigate, 1.5 m thick.
Notably, the pollen grains of Passiflora typically have large amounts of lipophilic substances associated with
exine (SOUZA et al., 2004) in the form of large drops (exudate) or with a fibrillar aspect between the free columellae of the reticulum, called pollenkitt (Figure 2F).
Pollutants make the surface of the
exine more fragile, triggering a mucosal reaction and making them more exposed to pollen allergens.
The pollen grains are light yellow, sticky, tricolporate with smooth
exine and 66.4 [micro]m in size (Fig.
The
exine is intectated with a scabrate or microgemate sculpturing (MOORE & al., 1991; Beug, 2004), and is very sensitive to corrosion (HAVINGA, 1964, 1967), so it is not a very common taxon in pollen records.
Mature pollen grain size,
exine sculpturing, and number of pores are the most distinctive features [6, 7].
18th Ave., for
Exine Anderson Bailey, a retired UO music professor and one of the first soloists to perform with the Oregon Bach Festival.