Which of the following best describes a carbohydrate?
a) carbohydrates are composed of amino acid monomers and are involved in cell signaling, cell transport, immune responses, and the cell cycle.
b) carbohydrates always consist of a five-carbon sugar, a nitrogenous base, and one or more phosphate groups and are used to store genetic information.
c) carbohydrates are organic macromolecules that are made up of carbon, hydrogen, and oxygen atoms and are used for energy storage or as structural molecules.
d) carbohydrates are organic macromolecules that are insoluble in water and have the ability to store energy for extended periods of time.

hydroxyl -oh

alcohols, always polar, can form hydrogen bonds with h2o molecules

carboxyl -cooh  

cargoxylic acids, has acidic properties which is a source of hydrogen ions, found in cells in ionized for with a charge of oh-1

carbonyl > co

ketone if within skeleton, aldehyde if group is at the end of skeleton, k & a may be structural isomers, it determines 2 sugars (ketose & aldose)

amino -nh2

amines, acts as a base, it can pick up h+ ions from surrounding solution, ionized with charge of 1+

methyl ch2

addition to rna/dna affects and gene expression

phosphate -opo3 ²⁻

organic phosphates, contributes to negative charge to, molecule that it is a part of, and potential to react with h20

sulfhydryl -sh

thiols, cross-linking stabilize the protein, and it is structure