FAILURE TO DETECT ASSOCIATION OF ISOLATED CLEFT PALATE WITH HLA ANTIGENS

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74079/1/j.1744-313X.1985.tb00853.x.pd

Ripening and dehiscence of the anther in some Crocus(Iridaceae) species

Abstract The anther development was examined in some Crocus species, by light and scanning electron microscopy. Epidermal cells develop a longitudinal stomium which is connected to the interlocular septum by cells with wide intercellular spaces.Endothecial cells are mono or bilayered, and they develop annular wall thickenings.Middle layer cells degenerate shortly after the microspore release. Tapetal cells are secretory with orbicules, and they form the tapetal membrane. The stomium disjoins from the interlocular septum after the lysis of the middle lamellae in the abscission region. The stomial cells break long before the flower opening, and in C. boryithey show signs of programmed cell death. Following the flower opening, the locular walls shrink tangentially, with flattening of epidermal cells and shortening of endothecial cells, and they bend up to turn inside out, exposing the pollen grains. The results are discussed in relation to the dehiscence mechanism