Colorized scanning electron micrograph depicts normal red blood cells (red, concave) with elongated blood cells indicative of sickle-cell disease (pink).

Image courtesy of Eye of Science/SPL.

Colorized scanning electron micrograph of human lung tissue, depicting alveoli and bronchus. Lung alveoli are tiny, grape-like sacs, numbering in the millions, where essential gas exchange (oxygen/carbon dioxide) occurs. The bronchus is a major airway that branches from the trachea to conduct air into the lungs.

Image courtesy of Dennis Kunkel/SPL.

Colorized scanning electron microscope composition of human sperm traveling through a fallopian tube.

Image courtesy of Steve Gschmeissner/Getty.

Carcinoma cells via fluorescence microscopy.

Image courtesy of Frederick Keeney, The Wistar Institute, Philadelphia.

Mouse brain vasculature, as imaged by light sheet fluorescence microscopy.

Image courtesy of Ali Erturk, Munich, Germany.

Stereomicrography of bacterial growth in a petri dish.

Image courtesy of Neil James Egan, PPG Industries, Cleveland, Ohio.

A human donor central retinal artery was cannulated (intubated) and perfused with Lectin FITC, a specific protein chemically linked to a fluorescent dye. The microvasculature of the optic nerve head area at the center is visible.

Image courtesy of Dong An, Lions Eye Institute, Australia.

Using confocal, deconvolution and image stacking techniques, a micrograph of a human I pluripotent stem cell-derived cardiac organoid.

Image courtesy of Syed Ashraf, Divya Sridharan and Salvia Zafar, Ohio State University.

A confocal micrograph of human neurons reprogrammed from skin cells.

Image courtesy of  Bruno Cisterna and Eric Vitriol, Medical College of Georgia at Augusta University.

A confocal micrograph of fluorescently marked mouse colon.

Image courtesy of Marius Mählen, Koen Oost, Prisca Liberali and Laurent Gelman, Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.