The inner and outer integuments elongated rapidly and almost enclosed the nucellus
Obturators, a transmitting plug of the placental region that facilitates entered of the polinic tube in the ovule, also occur in Liliaceae and some other groups; in Euphorbiaceae the obturator is in direct contact with the nucellus
(Endress, 1994; Souza, 2009; De-Paula and Sajo, 2011).
Indeed, the male flowers have a well-developed gynoecium with well-formed ovaries and ovules possessing normal integuments and a nucellus
, although we could not confirm a normal embryo sac.
as an experimental system in basic and applied tissue culture research.
Foraging strategies of dogwhelks, Nucellus
lapillus (L.): Interacting effects of age, diet and chemical cues to the threat of predation.
Until this study, no proteins have yet been documented, although Ziegler (1959) found acid phosphatase activity in the nucellus
, the sporogenous tissue that produces the pollination drop.
An archesporial cell in the nucellus
tissue would directly develop into a megasporocyte that subsequently formed the megaspore tetrads aftermeiosis.
In the region of the micropyle, cells of the two teguments and a layer of nucellus
with elongated cells present phenolic compounds forming the epistase (Figure 7e, g-h).
Modern seeds develop from a mature ovule, the female gametophyte being embedded within a fleshy nucellus
. One or more layers of the integuments, which develop into the seed coat, enclose the nucellus
The inner and outer integuments that appear around the periphery of the nucellus
of the angiosperm ultimately become the testa or seed coat of the mature ovule (Copeland, 1976).
All treatments act via one of the build-in areas of weakness in the seed coat, i.e., hilum, strophiole (a crestlike excrescence about the hilum), micropyle (opening through which the pollen tube enters), or chalaza (the region opposite the micropyle, where the integuments and nucellus
(central part in which the embryo sac develops) are joined) that either softens, cracks, ruptures, or collapses during treatment (Rolston, 1978, Baskin et al., 2000).