Shifting light spectra (IMAGE) Boston Children's Hospital Caption These Raman spectroscopy images show the intensity and wavelengths of reflected light from each of three cellular proteins -- mitochondrial cytochrome, myoglobin and hemoglobin -- when a laser is shined on the cell. The light spectra produced when the proteins are oxygenated are shown in red, de-oxygenated in blue. The different oxygen conditions cause differences in the bending and stretching of chemical bonds in the proteins' porphyrin rings, scattering the light differently. Raman spectroscopy thus provides an index of how much oxygen the mitochondria are receiving relative to the cell's energy needs. Credit Dr. John Kheir, Boston Children's Hospital & Shutterstock Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.