The only way is up. What appears to be manmade is actually a scanning electron micrograph of a growing calcite crystal. The apparent arrows on the surface are formed by the crystal’s natural growth and the way proteins bind.
Image courtesy of David Green.
What appears to be some sort of horrific deep-sea creature is, in fact, the microscopic image of Taenia solium, a species of pig tapeworm that can cause human infections if it or its eggs are consumed in undercooked pork. What appear to be eyes and mouth are actually suckers and a hook-lined rostellum used to grip and anchor to the wall of the human small intestine.
Image courtesy of Teresa A. Zgoda.
An artistic rendition of an Ishihara pattern comprised of more than 500 photographs of people’s retinas. An Ishihara pattern is a circular design made of randomized colored dots that hides a number or shape. It is used in eye tests to check for red-green color blindness.
Image courtesy of Jonathan Brett.
A colorized scanning electron micrograph cardiovascular calcification, showing a calcium phosphate spherical particle (orange) within the extracellular matrix. Abnormal calcium and phosphate levels in the blood promote hardening and narrowing of blood vessels.
A colorized scanning electron micrograph of the human spinal cord and dorsal root ganglia—clusters of sensory nerve cell bodies that relay touch, temperature, and pain signals from the body to the brain.
The aortic endothelium of a mouse (the thin, single layer of cells lining the inner surface of the aorta) stained for beta-catenin (green), laminin (purple), smooth muscle actin (red) and Hoechst (cyan), which binds to DNA.
Image courtesy of Florian Alonso, University of Bordeaux.
An adult transgenic zebrafish head reveals blood vessels (blue), lymphatic vessels (yellow) and skin and scales (magenta).
Image courtesy of Daniel Castranova and Brant M. Weinstein, NIH.
The subventricular zone of a mouse brain. This is the largest region where new neurons are born. The blood vessels (green) are important in regulating the behavior of neural stem cells, providing a vascular niche for neurogenesis.
Image courtesy of Terry Burns, Stanford University.
A single mast cell enters conjunctival tissue in the eye in response to an inflammatory agent or pathogen. Mast cells are among the first cells of the immune system to react to the presence of an invader, facilitating movement of leukocytes and other immune cells toward the site of infection through the release of histamines (red dots), which act as chemical messengers.
Image courtesy of Donald Pottle, The Schepens Eye Research Institute, Massachusetts.
The adult mouse hippocampus, a region of the brain involved in learning and memory, is depicted. Reactive astroglia cells (pale yellow) have proliferated and enlarged in response to neuronal activity over time.
Image courtesy of Sandra Dieni, Albert-Ludwigs University, Germany.