DENDROLOGY

Detailed explanation-1: -Carbohydrates contain only carbon, hydrogen and oxygen atoms; prior to any oxidation or reduction, most have the empirical formula Cm(H2O)n. Compounds obtained from carbohydrates by substitution, etc., are known as carbohydrate derivatives and may contain other elements.

Detailed explanation-2: -All carbohydrates, including sugar, therefore contain the same three elements: carbon, hydrogen and oxygen.

Detailed explanation-3: –Plants make carbohydrates from photosynthesis.-Photosynthesis requires sunlight, carbon dioxide, and water as starting materials. The reaction forms glucose and oxygen. The glucose is further stored in the form of starch in the plant.