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How are carotenes in carrots and green leaves related to hydrocarbons?

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structures of common hydrocarbon compounds — hydrocarbon Structures assumed by hydrogen (H) and carbon (C) molecules in four common hydrocarbon compounds.

Carotenes are directly classified as hydrocarbons because they belong to a specific chemical group of carotenoids composed entirely of this type of compound. Unlike xanthophylls, which are oxygenated, carotenes are unsaturated hydrocarbons containing many double bonds and belong to the isoprenoid series.123

In nature, these hydrocarbon pigments are widely distributed in plants. In carrots, they are responsible for the root's characteristic orange color. In the green leaves of plants, carotenes function as essential accessory pigments for photosynthesis, where they trap solar energy and transfer it to chlorophyll. Because they are hydrocarbons, these pigments are insoluble in water but dissolve readily in fat solvents. When ingested by animals, certain carotenes serve as important precursors that the liver converts into vitamin A.312