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Chemistry

The Mechanism of Photoisomerization in Retinal for Vision Signaling

Quick fact

The photoisomerization of 11-cis-retinal to all-trans-retinal happens in about 200 femtoseconds, making it one of the fastest biological reactions known.

Why this is interesting

You just saw a flash of light—but how did a photon of light, a particle with no mass, become an image in your brain? The secret lies in a single molecule that changes shape in less than a trillionth of a second.