BIOD101
M5 :Cell Signaling
LATEST EXAM READINESS
GUIDE
Q&S
©2024/2025
, 1. Which of the following molecules is a second
messenger?
a) ATP
b) Insulin
c) cAMP
d) DNA
Answer: c) cAMP
Rationale: Cyclic AMP (cAMP) is a second messenger
used for intracellular signal transduction in many biological
processes.
2. Protein kinases are crucial in signaling pathways
because they:
a) Directly activate genes
b) Hydrolyze phospholipids
c) Phosphorylate proteins
d) Degrade proteins
Answer: c) Phosphorylate proteins
Rationale: Protein kinases add phosphate groups to
proteins, often activating or deactivating them, which is vital
for signal transduction.
3. Which signaling pathway primarily involves G-protein
coupled receptors (GPCRs)?
a) Steroid hormone signaling
b) Ras/MAPK pathway
c) Wnt signaling
d) Adenylate cyclase pathway
Answer: d) Adenylate cyclase pathway
Rationale: GPCRs are involved in many pathways, but the
adenylate cyclase pathway specifically involves G-proteins
©2024/2025
, activating adenylate cyclase.
4. What is the role of phosphatases in cell signaling?
a) Phosphorylate substrates
b) Deactivate cAMP
c) Remove phosphate groups
d) Bind to receptors
Answer: c) Remove phosphate groups
Rationale: Phosphatases remove phosphate groups,
counteracting the action of kinases.
5. Which molecule can act both as a neurotransmitter
and a hormone?
a) Acetylcholine
b) Dopamine
c) Noradrenaline
d) Histamine
Answer: c) Noradrenaline
Rationale: Noradrenaline functions as a neurotransmitter in
the nervous system and as a hormone in the bloodstream.
6. In the context of cell signaling, what is apoptosis?
a) Cell division
b) Programmed cell death
c) Uncontrolled cell growth
d) Cellular differentiation
Answer: b) Programmed cell death
Rationale: Apoptosis is a process of programmed cell
death, which is often regulated by signaling pathways.
7. What is the main function of the Ras protein in
signaling pathways?
a) Initiate gene transcription
©2024/2025
M5 :Cell Signaling
LATEST EXAM READINESS
GUIDE
Q&S
©2024/2025
, 1. Which of the following molecules is a second
messenger?
a) ATP
b) Insulin
c) cAMP
d) DNA
Answer: c) cAMP
Rationale: Cyclic AMP (cAMP) is a second messenger
used for intracellular signal transduction in many biological
processes.
2. Protein kinases are crucial in signaling pathways
because they:
a) Directly activate genes
b) Hydrolyze phospholipids
c) Phosphorylate proteins
d) Degrade proteins
Answer: c) Phosphorylate proteins
Rationale: Protein kinases add phosphate groups to
proteins, often activating or deactivating them, which is vital
for signal transduction.
3. Which signaling pathway primarily involves G-protein
coupled receptors (GPCRs)?
a) Steroid hormone signaling
b) Ras/MAPK pathway
c) Wnt signaling
d) Adenylate cyclase pathway
Answer: d) Adenylate cyclase pathway
Rationale: GPCRs are involved in many pathways, but the
adenylate cyclase pathway specifically involves G-proteins
©2024/2025
, activating adenylate cyclase.
4. What is the role of phosphatases in cell signaling?
a) Phosphorylate substrates
b) Deactivate cAMP
c) Remove phosphate groups
d) Bind to receptors
Answer: c) Remove phosphate groups
Rationale: Phosphatases remove phosphate groups,
counteracting the action of kinases.
5. Which molecule can act both as a neurotransmitter
and a hormone?
a) Acetylcholine
b) Dopamine
c) Noradrenaline
d) Histamine
Answer: c) Noradrenaline
Rationale: Noradrenaline functions as a neurotransmitter in
the nervous system and as a hormone in the bloodstream.
6. In the context of cell signaling, what is apoptosis?
a) Cell division
b) Programmed cell death
c) Uncontrolled cell growth
d) Cellular differentiation
Answer: b) Programmed cell death
Rationale: Apoptosis is a process of programmed cell
death, which is often regulated by signaling pathways.
7. What is the main function of the Ras protein in
signaling pathways?
a) Initiate gene transcription
©2024/2025
