MCQ
Natural dyes and pigments MCQ - Practice Questions with Answers
Solve 1 Natural dyes and pigments questions for RAS/RPSC preparation.
Practice questions
Q1Which of the following is responsible for the dark brown or reddish colour given by henna?
Explanation
Lawsone is the dye molecule in henna leaves that binds with proteins in skin, hair or nails and gives the familiar orange-red to dark brown stain. Luciferin is a light-emitting compound associated with bioluminescence, not henna colour. Melanin is the natural pigment found in skin and hair, but it is not the colouring agent released by henna. Hydroquinone is a different phenolic compound used in other chemical contexts and is not the main henna dye. The stain is therefore attributed to lawsone.
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