Light micrograph of Purkinje neurons (light blue) in the cerebellum. Nerve cells of the brain act collectively to process information needed for proper cognitive functioning. (Credit: Steve Gschmeissner/Science Photo Library/Alamy Stock Photo)
Transection from the outer part of a Smilax root, illustrating a thick-walled hypodermis (exodermis) beneath the epidermis. One hypodermal cell is not thickened. (After K. Esau, Plant Anatomy, 2d ed., John Wiley and Sons, 1965)
Segmentation of Limulus polyphemus. Inconclusive evidence indicates that there are 15 segments (6 in the prosoma, 9 in the opisthosoma). The telson (XV) may be a terminal spine that has become articulated and has incorporated the anus into its base.