Spore
A reproductive cell of a fungus, analogous in function to a seed but structurally far simpler.
A spore is a reproductive cell capable of developing into a new fungal organism without fertilization. Spores are analogous to seeds in their function but far smaller and structurally simpler — a typical agaric spore is 5 to 20 micrometers long.
A single mature mushroom can release tens of millions of spores. They are produced on specialized cells called basidia that line the underside of the cap and are released through a mechanism called the Buller’s drop, which uses a small water droplet to launch each spore clear of the gill edge.
The color of a spore print — made by laying a mature cap gills-down on paper for several hours — is a key identification character. Psilocybe spore prints are dark purple-brown, Agaricus prints are chocolate, and Amanita prints are white.