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Lehninger Principles of BioChem
Chapter 21 Final Actual Exam Brand
New 2026
Three-carbon donor used in fatty acid synthesis. Formed from acetyl-
CoA by acetyl-CoA carboxylase. Inhibits CPT1. --Verified--Solution----
Malonyl-CoA
Rate-limiting enzyme of fatty acid synthesis. Converts acetyl-CoA →
malonyl-CoA. Activated by insulin, inhibited by glucagon/AMPK. --
Verified--Solution----Acetyl-CoA carboxylase (ACC)
Large multifunctional enzyme complex that builds palmitate (16:0) from
acetyl-CoA and malonyl-CoA using NADPH. --Verified--Solution----
Fatty acid synthase (FAS)
Component of FAS that holds the growing fatty acid chain via a
phosphopantetheine arm. --Verified--Solution----Acyl carrier protein
(ACP)
Flexible prosthetic group attached to ACP that carries acyl intermediates
during synthesis. --Verified--Solution----4′-Phosphopantetheine
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ER enzymes that extend fatty acids beyond 16 carbons --Verified--
Solution----Fatty acid elongation systems
Introduces double bonds into fatty acyl-CoA chains (in ER). --Verified--
Solution----Fatty acyl-CoA desaturase
Enzymes that insert one atom of oxygen into substrate and reduce the
other to water (often NADPH-dependent). --Verified--Solution----
Mixed-function oxidases / oxygenases
Introduces first double bond into saturated fatty acids (e.g., stearate →
oleate). --Verified--Solution----Stearoyl-ACP desaturase (SCD)
20:4 fatty acid derived from linoleic acid. Precursor to eicosanoids. --
Verified--Solution----Arachidonate (arachidonic acid)
Lipid signaling molecules derived from arachidonic acid. Regulate
inflammation, pain, fever. --Verified--Solution----Prostaglandin (PG)
Enzyme that converts arachidonic acid → prostaglandin intermediates.
Target of NSAIDs. --Verified--Solution----Cyclooxygenase (COX)
Converts DHAP ↔ glycerol 3-phosphate for TAG and phospholipid
synthesis. --Verified--Solution----Glycerol 3-phosphate dehydrogenase
Lehninger Principles of BioChem
Chapter 21 Final Actual Exam Brand
New 2026
Three-carbon donor used in fatty acid synthesis. Formed from acetyl-
CoA by acetyl-CoA carboxylase. Inhibits CPT1. --Verified--Solution----
Malonyl-CoA
Rate-limiting enzyme of fatty acid synthesis. Converts acetyl-CoA →
malonyl-CoA. Activated by insulin, inhibited by glucagon/AMPK. --
Verified--Solution----Acetyl-CoA carboxylase (ACC)
Large multifunctional enzyme complex that builds palmitate (16:0) from
acetyl-CoA and malonyl-CoA using NADPH. --Verified--Solution----
Fatty acid synthase (FAS)
Component of FAS that holds the growing fatty acid chain via a
phosphopantetheine arm. --Verified--Solution----Acyl carrier protein
(ACP)
Flexible prosthetic group attached to ACP that carries acyl intermediates
during synthesis. --Verified--Solution----4′-Phosphopantetheine
, 2 | Page
ER enzymes that extend fatty acids beyond 16 carbons --Verified--
Solution----Fatty acid elongation systems
Introduces double bonds into fatty acyl-CoA chains (in ER). --Verified--
Solution----Fatty acyl-CoA desaturase
Enzymes that insert one atom of oxygen into substrate and reduce the
other to water (often NADPH-dependent). --Verified--Solution----
Mixed-function oxidases / oxygenases
Introduces first double bond into saturated fatty acids (e.g., stearate →
oleate). --Verified--Solution----Stearoyl-ACP desaturase (SCD)
20:4 fatty acid derived from linoleic acid. Precursor to eicosanoids. --
Verified--Solution----Arachidonate (arachidonic acid)
Lipid signaling molecules derived from arachidonic acid. Regulate
inflammation, pain, fever. --Verified--Solution----Prostaglandin (PG)
Enzyme that converts arachidonic acid → prostaglandin intermediates.
Target of NSAIDs. --Verified--Solution----Cyclooxygenase (COX)
Converts DHAP ↔ glycerol 3-phosphate for TAG and phospholipid
synthesis. --Verified--Solution----Glycerol 3-phosphate dehydrogenase
