In the Gram-stain procedure, Gram-negative, but not Gram-positive, cell wall structures are decolorized because

because the structure of their cell wall is unable to retain the crystal violet stain

Explanation:

Due to differences in the thickness of a peptidoglycan layer in the cell membrane between Gram-positive and Gram-negative bacteria, Gram-positive bacteria (with a thicker peptidoglycan layer) retain crystal violet stain during the decolorization process, while Gram-negative bacteria lose the crystal violet stain

one part of the electromagnetic spectrum that arrives on earth as solar radiation from the sun is the visible spectrum. wavelengths of the visible spectrum combine to form what we refer to as

answer - d) ultraviolet radiation.

violet /   380–450 nm / 668–789 thz

violet is number 1 in the chart of visible light.