In contrast to Slide 1, this image is from a small intestine that was fixed for electron microscopy, which generally yields better preservation than routine light microscopic fixatives such as formalin. Such specimens are also embedded in plastic. Paraffin sections generally are 5-12 μm thick while plastic embedded sections are usually from 0.5 μm to 1.5 μm thick. Thinner sections appear sharper (compare the detail with Slide 1). Some plastic embedded sections are stained with toluidine blue without another (counter) stain such as can be seen in this image. Since the section is much thinner, many components stain more lightly (look at the nuclei, for example; compare with Slide 1).