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In the conjugated chromophores, the electrons jump between energy levels that are extended pi orbitals, created by electron clouds like those in aromatic systems. Common examples include retinal (used in the eye to detect light), various food colorings, fabric dyes (azo compounds), pH indicators, lycopene, β-carotene, and anthocyanins. Various ...
Examples include the hydroxyl (−OH), amino (−NH 2), aldehyde (−CHO), and methyl mercaptan groups (−SCH 3). [ 2 ] An auxochrome is a functional group of atoms with one or more lone pairs of electrons when attached to a chromophore, alters both the wavelength and intensity of absorption .
It is known in zebrafish embryos, for example, that by 3 days after fertilization each of the cell classes found in the adult fish—melanophores, xanthophores and iridophores—are already present. Studies using mutant fish have demonstrated that transcription factors such as kit , sox10 , and mitf are important in controlling chromatophore ...
Retinal is a conjugated chromophore.In the Vertebrate eyes, retinal begins in an 11-cis-retinal configuration, which — upon capturing a photon of the correct wavelength — straightens out into an all-trans-retinal configuration.
Two examples of carotenoids are lycopene and β-carotene. These molecules also absorb light most efficiently in the 400 – 500 nm range. Due to their absorption region, carotenoids appear red and yellow and provide most of the red and yellow colours present in fruits and flowers. The carotenoid molecules also serve a safeguarding function.
Most molecules and ions absorb energy in the ultraviolet or visible range, i.e., they are chromophores. The absorbed photon excites an electron in the chromophore to higher energy molecular orbitals, giving rise to an excited state. [7] For organic chromophores, four possible types of transitions are assumed: π–π*, n–π*, σ–σ*, and n ...
What happens after an executive order is signed? After a president signs an executive order, the White House sends the document to the Office of the Federal Register, the executive branch's ...
In a reactive dye, a chromophore (an atom or group whose presence is responsible for the colour of a compound) contains a substituent that reacts with the substrate. Reactive dyes have good fastness properties owing to the covalent bonding that occurs during dyeing.