NST 103 Midterm 3 (E) Exam 2025
Questions and Answers
What are the 2 key "Ketogenic" intermediates involved in amino acid degradation? -
ANSWER✔✔-- Acetoacetyl-CoA
- Acetyl-CoA
What are the 5 "Glucogenic" intermediates involved in amino acid degradation? (hint:
TCA) - ANSWER✔✔-- pyruvate
- a-ketoglutarate
- succinyl-coA
- fumarate
- oxaloacetate
Which organs does FA synthesis occur? - ANSWER✔✔-adipose tissue, liver, and
lactating mammary gland
Where does FA synthesis occur? - ANSWER✔✔-cytosol
,When does FA synthesis occur? - ANSWER✔✔-when the availability of acetyl CoA
exceeds needs for energy
What are the substrates of FA synthesis? - ANSWER✔✔-glucose & amino acids
What is primary carrier of acetyl coA into the cytosol? - ANSWER✔✔-citrate
Where is Acetyl CoA produced? - ANSWER✔✔-mitochondria
Can Acetyl CoA cross the inner mitochondrial membrane? - ANSWER✔✔-no
Where are the transporters for citrate present? - ANSWER✔✔-mitochondrial membrnae
List the pathway of pyruvate to FAS (mitochondria --> cytosol) - ANSWER✔✔-
pyruvate --> acetyl coA --> citrate --> citrate --> OAA + Acetyl-CoA --> FAS
What is the initiation reaction of the synthesis of palmitate from acetyl coA? (name the
enzyme & substrates) - ANSWER✔✔-- acetyl coA --> acetyl ACP
- enzyme: ACP-SH --> CoA-SH
What is the activation reaction of the synthesis of palmitate from acetyl coA? -
ANSWER✔✔-- acetyl CoA --> malonyl coA
- enzyme: acetyl CoA carboxylase (ACC) (w/biotin)
, ______________ elongates _____________ to produce palmitoyl-ACP & it inhibits
________ which keeps FA's in the cytosol. - ANSWER✔✔-Malonyl-CoA, acetyl-ACP,
CPT1
To make one palmitate molecule, how many cycles are required? - ANSWER✔✔-7
To make 1 palmitate molecule, what are the input molecules of round 1? -
ANSWER✔✔-2C acetyl-ACP, malonyl-CoA
For De Novo palmitate synthesis, what are the substrates? (list exact number of them
too) - ANSWER✔✔-- 1 acetyl coA
- 7 malonyl CoA
- 14 NADPH
- 14 H+
For De Novo Palmitate synthesis, what are the products? (list the exact number too) -
ANSWER✔✔-- 1 palmitate
- 7 CO2
- 14 NADP+
- 7 H2O
Which reaction requires biotin? - ANSWER✔✔-the production of malonyl coA
Questions and Answers
What are the 2 key "Ketogenic" intermediates involved in amino acid degradation? -
ANSWER✔✔-- Acetoacetyl-CoA
- Acetyl-CoA
What are the 5 "Glucogenic" intermediates involved in amino acid degradation? (hint:
TCA) - ANSWER✔✔-- pyruvate
- a-ketoglutarate
- succinyl-coA
- fumarate
- oxaloacetate
Which organs does FA synthesis occur? - ANSWER✔✔-adipose tissue, liver, and
lactating mammary gland
Where does FA synthesis occur? - ANSWER✔✔-cytosol
,When does FA synthesis occur? - ANSWER✔✔-when the availability of acetyl CoA
exceeds needs for energy
What are the substrates of FA synthesis? - ANSWER✔✔-glucose & amino acids
What is primary carrier of acetyl coA into the cytosol? - ANSWER✔✔-citrate
Where is Acetyl CoA produced? - ANSWER✔✔-mitochondria
Can Acetyl CoA cross the inner mitochondrial membrane? - ANSWER✔✔-no
Where are the transporters for citrate present? - ANSWER✔✔-mitochondrial membrnae
List the pathway of pyruvate to FAS (mitochondria --> cytosol) - ANSWER✔✔-
pyruvate --> acetyl coA --> citrate --> citrate --> OAA + Acetyl-CoA --> FAS
What is the initiation reaction of the synthesis of palmitate from acetyl coA? (name the
enzyme & substrates) - ANSWER✔✔-- acetyl coA --> acetyl ACP
- enzyme: ACP-SH --> CoA-SH
What is the activation reaction of the synthesis of palmitate from acetyl coA? -
ANSWER✔✔-- acetyl CoA --> malonyl coA
- enzyme: acetyl CoA carboxylase (ACC) (w/biotin)
, ______________ elongates _____________ to produce palmitoyl-ACP & it inhibits
________ which keeps FA's in the cytosol. - ANSWER✔✔-Malonyl-CoA, acetyl-ACP,
CPT1
To make one palmitate molecule, how many cycles are required? - ANSWER✔✔-7
To make 1 palmitate molecule, what are the input molecules of round 1? -
ANSWER✔✔-2C acetyl-ACP, malonyl-CoA
For De Novo palmitate synthesis, what are the substrates? (list exact number of them
too) - ANSWER✔✔-- 1 acetyl coA
- 7 malonyl CoA
- 14 NADPH
- 14 H+
For De Novo Palmitate synthesis, what are the products? (list the exact number too) -
ANSWER✔✔-- 1 palmitate
- 7 CO2
- 14 NADP+
- 7 H2O
Which reaction requires biotin? - ANSWER✔✔-the production of malonyl coA
