Petri dish

A Petri dish was a small, shallow container used for growing cells, used in biology and medicine.

In 2369 Lieutenant Jadzia Dax used a Petri dish to store and examine the samples she took from under Rao Vantika's fingernails. 

When infected with an alien virus forcing Kathryn Janeway and Chakotay to live on New Earth, Janeway collected several supplies, including Petri dishes, a protein analyzer, and DNA sequencers to continue her research in finding a cure. 

Upon discovering that the Srivani had infiltrated the USS Voyager in 2374 to conduct their medical experiments, The Doctor remarked that it was as if the ship were "one big Petri dish." 

In 2375, Captain Kathryn Janeway told Seven of Nine to make more nanoprobes with which to counter Species 8472 by whatever means necessary, whether they were extracted from her bloodsteam or grown in a Petri dish. 

To punish his son's misbehavior in 2378, Q transformed him into an Oprelian amoeba and confined him to a Petri dish.