BIOD101
M1: Biochemistry & Cell Biology
LATEST EXAM READINESS
GUIDE
Q&S
©2024/2025
,1. Which enzyme is responsible for catalyzing the first step
in glycolysis by converting glucose into glucose-6-
phosphate?
- A) Hexokinase
- B) Phosphofructokinase
- C) Pyruvate kinase
- D) Aldolase
Answer: A) Hexokinase
Rationale: Hexokinase catalyzes the phosphorylation of
glucose to glucose-6-phosphate, an essential first step in
glycolysis.
2. Which of the following molecules serves as the primary
electron carrier between Complex III and Complex IV of the
electron transport chain?
- A) NADH
- B) FADH2
- C) Cytochrome c
- D) Ubiquinone
Answer: C) Cytochrome c
Rationale: Cytochrome c is a soluble electron carrier that
transfers electrons between Complex III (cytochrome bc1
complex) and Complex IV (cytochrome c oxidase) in the
electron transport chain.
3. In the context of signal transduction, what is the primary
role of G protein-coupled receptors (GPCRs)?
- A) To directly regulate gene expression
- B) To facilitate the exchange of GDP for GTP
- C) To phosphorylate proteins
- D) To hydrolyze ATP
Answer: B) To facilitate the exchange of GDP for GTP
©2024/2025
, Rationale: GPCRs facilitate the exchange of GDP for
GTP on the Gα subunit of the heterotrimeric G protein,
activating the signaling pathway.
### Fill-in-the-Blank
4. The ___ cycle is a series of enzymatic reactions that
produces acetyl-CoA from fatty acids, NADH, and FADH2.
Answer: β-oxidation
Rationale: β-oxidation refers to the metabolic pathway
that breaks down fatty acids into acetyl-CoA, NADH, and
FADH2 for energy production.
5. In the Calvin cycle, the enzyme ___ catalyzes the
carboxylation of ribulose-1,5-bisphosphate.
Answer: Ribulose bisphosphate carboxylase/oxygenase
(RuBisCO)
Rationale: RuBisCO is the enzyme responsible for the
carboxylation of ribulose-1,5-bisphosphate in the Calvin
cycle of photosynthesis.
6. The process of ___ involves the conversion of glucose
into pyruvate with the production of ATP and NADH.
Answer: Glycolysis
Rationale: Glycolysis is the metabolic pathway that
converts glucose into pyruvate while yielding ATP and
NADH.
### True/False
7. True or False: DNA replication is bidirectional and starts
from a single origin of replication in eukaryotic cells.
Answer: False
©2024/2025
M1: Biochemistry & Cell Biology
LATEST EXAM READINESS
GUIDE
Q&S
©2024/2025
,1. Which enzyme is responsible for catalyzing the first step
in glycolysis by converting glucose into glucose-6-
phosphate?
- A) Hexokinase
- B) Phosphofructokinase
- C) Pyruvate kinase
- D) Aldolase
Answer: A) Hexokinase
Rationale: Hexokinase catalyzes the phosphorylation of
glucose to glucose-6-phosphate, an essential first step in
glycolysis.
2. Which of the following molecules serves as the primary
electron carrier between Complex III and Complex IV of the
electron transport chain?
- A) NADH
- B) FADH2
- C) Cytochrome c
- D) Ubiquinone
Answer: C) Cytochrome c
Rationale: Cytochrome c is a soluble electron carrier that
transfers electrons between Complex III (cytochrome bc1
complex) and Complex IV (cytochrome c oxidase) in the
electron transport chain.
3. In the context of signal transduction, what is the primary
role of G protein-coupled receptors (GPCRs)?
- A) To directly regulate gene expression
- B) To facilitate the exchange of GDP for GTP
- C) To phosphorylate proteins
- D) To hydrolyze ATP
Answer: B) To facilitate the exchange of GDP for GTP
©2024/2025
, Rationale: GPCRs facilitate the exchange of GDP for
GTP on the Gα subunit of the heterotrimeric G protein,
activating the signaling pathway.
### Fill-in-the-Blank
4. The ___ cycle is a series of enzymatic reactions that
produces acetyl-CoA from fatty acids, NADH, and FADH2.
Answer: β-oxidation
Rationale: β-oxidation refers to the metabolic pathway
that breaks down fatty acids into acetyl-CoA, NADH, and
FADH2 for energy production.
5. In the Calvin cycle, the enzyme ___ catalyzes the
carboxylation of ribulose-1,5-bisphosphate.
Answer: Ribulose bisphosphate carboxylase/oxygenase
(RuBisCO)
Rationale: RuBisCO is the enzyme responsible for the
carboxylation of ribulose-1,5-bisphosphate in the Calvin
cycle of photosynthesis.
6. The process of ___ involves the conversion of glucose
into pyruvate with the production of ATP and NADH.
Answer: Glycolysis
Rationale: Glycolysis is the metabolic pathway that
converts glucose into pyruvate while yielding ATP and
NADH.
### True/False
7. True or False: DNA replication is bidirectional and starts
from a single origin of replication in eukaryotic cells.
Answer: False
©2024/2025
