I need an example of drawing of a protein, carbohydrate and nucleic acid monomer. Also a saturated, monounsaturated and a polyunsaturated fatty acid.

1 Answer | Add Yours

ncchemist's profile pic

ncchemist | eNotes Employee

Posted on

You are basically asking about the four different types of biomolecules found in nature.  They are proteins, nucleic acids, carbohydrates, and lipids.

Proteins are polymeric chains of amino acids.  So amino acids are the monomers.  Amino acids are composed of a central carbon attached to a carboxylic acid, an amine, a hydrogen, and a side chain.  The nature of the side chain determines the exact nature of the amino acid.  Most proteins are composed of different sequences of 20 basic amino acids.

Nucleic acids are polymeric chains of nucleotides.  Nucleotides are composed of a ribose sugar, a phosphate group, and a nitrogenous base.  DNA and RNA are both composed of four different nucleotides.  Three of them are shared between both of them (A, C, and G), while the fourth one is unique to each species (T for DNA and U for RNA).

Carbohydrates are polymers of sugars.  Sugars are a little harder to specifically define.  They are composed of carbon, hydrogen, and oxygen and have a general empirical formula of CH2O.  Sugars consist of small chains of carbon that can either be linear or cyclic and the carbons have numerous hydroxyl groups attached.  Fructose and glucose are common examples.

Lipids are basically fats.  They are different in that they are not really polymers.  Fats have a glycerol base that is connected to 1 to 3 fatty acids, which are long hydrocarbon chains.  Fatty acids that have only carbon carbon single bonds are called saturated because they are saturated with hydrogen atoms.  Fatty acids with one carbon carbon double bond are called monounsaturated and with more then one double bond are called polyunsaturated.

I cannot draw examples here but follow the links below for more structural information.

We’ve answered 319,849 questions. We can answer yours, too.

Ask a question