Pollen

According to the Eleventh Doctor, pollen was collected by bees. (TV: Closing Time)

Psychic pollen was found in the Candle Meadows of Karass Don Slava. (TV: Amy's Choice)

An alcoholic beverage was brewed from fermented pollen of mutant space bees. (PROSE: Original Sin)

Cyber-pollen were particles that could convert compatible organic matter, living or dead, into Cybermen. (TV: Death in Heaven)

A speck of Vervoid pollen penetrated a minute scratch on Ruth Baxter's thumb, resulting in her mutating into a Vervoid hybrid. (TV: Terror of the Vervoids)