Functional Groups & Linkages

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hydroxyl group (OH)

→ called alcohols

carboxyl group (COOH)

→ called carboxylic acids

carbonyl group

→ aldehyde (at the end of the carbon skeleton)

→ ketone (in the middle of the carbon skeleton)

phosphate group (PO4)

→ used in energy transfers

→ ATP to ADP and vice versa

sulfhydryl group (SH)

→ found in proteins

amino group (NH2)

→ found in amino acids

ether linkage

→ between 2 alcohols

→ NOTE: for this linkage, and all the other ones, it's only when water is removed between the 2 mentioned molecules (dehydration synthesis)

ester linkage

→ between alcohol and carboxyl

OR

→ between alcohol and acid

anhydride linkage

→ between 2 carboxyl groups

OR

→ between 2 phosphate groups

phosphate ester linkage

→ between a phosphate and an alcohol

peptide linkage

→ between the amino of one amino acid and the carboxyl of another amino acid