(-OH), a hydrogen atom is bonded to an oxygen atom, which in turn is bonded to the carbon skeleton of the organic molecule.
 ( ⟩C=O), consists of a carbon atom joined to an oxygen atom by a double bond.
Hydroxyl Group-Functional Properties
 Is polar as a result of the electronegative oxygen atom drawing electrons toward itself
 Attracts water molecules, helping dissolve organic compounds such a sugars
 Name of Compound: Ketones (if the ******** group is within a carbon skeleton)
 Name of Compound: Aldehydes (if the ******** group is at the end of the carbon skeleton)
Carbonyl Group-Functional Properties
 A ketone & aldehyde may be structural isomers with different properties, as is the case for acetone and propanal.
 (O=C-OH) When an oxygen atom is double bonded to a carbon atom that is also bonded to a hydroxyl group. **Carbon is asymmetrical: O & -OH are branched of of C which is attached to the specific skeleton
Carboxyl Group-Functional Properties
 Has acidic properties because it is a source of hydrogen ions
 The covalent bond between O & H is so polar that Hydrogen ions (H⁺) tend to dissociate reversibly
 In cells, found in the Ionic form, which is called a carboxylate group.
 (-N ⟩ H or -NH2) Consists of a nitrogen atom bonded to two hydrogen atoms and to the carbon skeleton
Amino Group-Functional Properties
 Acts as a base; can pick up a proton from the surrounding solution(s):
(a). N bonded to 2 hydrogens (nonionized)
(b). N⁺ bonded to 3 Hydrogens (ionized)
 Ionized, with a charge of 1+, under cellular conditions
 (-SH) Consists of a sulfur atom bonded to an atom of hydrogen; resembles a hydroxyl group in shape
Sulfhydrl Groups-Functional Properties
 Two of this specific type of group(s) can interact to stabilize a protein structure
 A phosphorous atom is bonded to four oxygen atoms; one oxygen is bonded to the carbon skeleton; two oxygens carry negative charges. 'Top' oxygen is double bonded to the Phosphorous atom
 (-OPO₃²-) is an ionized form of a phosphoric acid group (-OPO₃H₂; note the two hydrogens).