Follow your curiosity

What discovery has been shared with you?

FACTREE gives you something interesting to discover every day — and something worth talking about together.

Start with one fact. Explore it, go deeper, then follow whichever branch catches your imagination.

Choose subjects for a surprise

Exploring any topic

Begin your discovery

Your next discovery is one click away.

Choose one or more subjects above, or leave Any Topic selected and let curiosity decide.

Biology

Culture Media Selection for Bacterial Pathogen Identification

Quick fact

MacConkey agar not only selects for Gram-negative bacteria but also turns pink if the bacterium ferments lactose, instantly distinguishing Escherichia coli from Salmonella.

Why this is interesting

If you take a swab from a sick patient and spread it on a plate of food for bacteria, you'd get a messy mix—yet microbiologists can pick out the villain in a single day. The trick lies in the ingredients they choose.