Section of yellow onion when exposed to regular ...

The image presents a striking comparison between two sections of yellow onions, one exposed to regular daylight and the other illuminated by a 365 nm ultraviolet (UV-A) blacklight from HEB supermarket.

**Section Exposed to Regular Daylight**

* The top half of the image displays a section of yellow onion cut open.
* The onion is illuminated by natural light, which accentuates its yellow color.
* The layers of the onion are visible, showcasing its layered structure.
* The onion appears pale and translucent due to the absence of UV-A radiation.

**Section Illuminated by 365 nm Ultraviolet (UV-A) Blacklight**

* The bottom half of the image shows a section of the same yellow onion, this time illuminated by a 365 nm UV-A blacklight from HEB supermarket.
* Under the UV-A light, the onion exhibits a vibrant blue coloration.
* The layers of the onion are more pronounced than in the daylight-exposed section, with each layer displaying a distinct blue hue.
* The UV-A radiation has caused the formation of fluorescent compounds within the onion, which emit light at 365 nm.

**Comparison and Conclusion**

The image highlights the significant difference in appearance between the two sections of yellow onions. While the daylight-exposed section appears pale and translucent, the UV-A-illuminated section displays a vibrant blue coloration due to the presence of fluorescent compounds that emit light at 365 nm. This phenomenon demonstrates the unique interaction between UV-A radiation and biological materials, leading to the formation of visible light in certain wavelengths. – AI vision