- Alcohols contain an -OH group, which is polar and hydrophilic due to it's electronegative O atom. Molecules with many -OH dissolve easily in water.
- Thiols have an -SH group, which is polar and hydeophilic due to it's electronegative S atom. Certain amino acids, the building blocks of proteins, contain -SH groups, which help dtabilize the shape f the proteins.
- amino acid cysteine.
contain a carbonyl group within the carbon skeleton. The carbonyl group is polar and hydrophilic due to it's electronegative O atom.
- R R or
- Aldehydes Have a carbonyl group at the end of the carbon skeleton.
- Carboxylic acids contain a arboxyl group at the end of the carbon skeleton. all amino acids have a -COOH
- group at one end. The negatively charged form predominates at the pH of body cells and is hydrophilic.
- OR O
- / \
- R OH
- Ester Predominate in dietary dats and oils and also occur in our body triglycerides. Asprin is an ester of salicylic acid, a pain reliever molecule found in the bark of a willow tree.
- Phospheates contain a a phosphate group (-PO2- 4) which is very hydrophilic due to the dual negative charges.
- An important example is adenosine riphosphate (ATP), which transfers chemical energy between organic molecules during chemical reactions. (DNA,RNA)
have an -NH2 group, which can as a base and pick up a hydrogen ion
, giving the amino group a positive charge. At pH of the body fluids, most amino groups have a charge of 1+. All amino acids have an amino group at one end.
- + /