A new kind of microscope is giving scientists a way to watch life inside cells with a clarity that feels almost unfair.

YEAST CELLS — Brewing yeast cells are seen under a microscope as part of a study on nonalcoholic beer. Credit must be given to the creator. Only noncommercial uses of the work are permitted.

When a maize plant is attacked by the fungus Ustilago maydis, tumor-like tissue growths occur at the site of infection. How the pathogen causes this response in its host has long been unknown. But a ...