PATHOLOGY

Detailed explanation-1: -Plants contain a variety of such compounds, but the most common are -carotene (pronounced beta-carotene, the same pigment responsible for coloring carrots orange) and lutein (a yellow compound at low concentrations, but orange-red when concentrated) as well as some others described below.

Detailed explanation-2: -Carotenoids are tetraterpene pigments, which exhibit yellow, orange, red and purple colors.

Detailed explanation-3: -In general, carotenoids absorb wavelengths ranging from 400 to 550 nanometers (violet to green light). This causes the compounds to be deeply colored yellow, orange, or red.