Pollen as large as about 90–100 µm. In angiosperms, during flower development the anther is composed of a mass of cells that appear undifferentiated, except for a partially differentiated dermis. As the flower develops, four groups of sporogenous cells form within the anther. The fertile sporogenous cells are surrounded by layers of sterile cells that grow into the wall of the pollen sac. Some of the cells grow into nutritive cells that supply nutrition for the microspores that form by meiotic division from the sporogenous cells. In a process called microsporogenesis, four haploid microspores are produced from each diploid sporogenous cell
Shroud of Turin should be suspended until a new collection of pollen grains can be carried out and the grains thus obtained can be studied with modern equipment and by an expert of pollen of this area." Skeptics have argued that the flower images are too faint for Danin's determination to be definite, that an independent review of the pollen strands showed that one strand out of the 26 provided contained significantly more pollen than the others, perhaps pointing to deliberate contamination. Skeptics also argue that Max Frei had previously been duped in his examination of the Hitler Diaries and that he may