Twenty sequential and adjacent visual fields from each EM slide were imaged at a magnification of 8800. Total area of the ER whorls in 20 visual fields of electron microscope was measured with ImageJ (NIH), which covered a total area of 3335 mm 2 . Only ER membrane structures containing more than four membrane stacks were considered to be whorls and used for area measurements. The data were statistically analyzed as pixels per 20 visual fields using Pearson Chi-square test with SPSS for Windows (v11.5).