BIOD 322 Module 2: Synaptic Transmission and
Neurotransmitters Exam 2026/2027 UPDATE UPDATED
ACTUAL Questions and CORRECT Answers
1. Which of the following is a key characteristic of electrical synapses?
A. They utilize neurotransmitters to bridge the gap
B. They allow for nearly instantaneous signal transmission
C. They are wider than chemical synapses
D. They involve a significant synaptic delay
Answer: B
Rationale: Electrical synapses use gap junctions to allow direct ionic current flow,
resulting in high speed and minimal delay.
2. What is the approximate width of the synaptic cleft in a chemical synapse?
A. 1-2 nm
B. 5-10 nm
C. 20-50 nm
D. 100-200 nm
Answer: C
Rationale: The synaptic cleft in chemical synapses is typically between 20 and 50
nanometers wide.
,3. Where are small-molecule neurotransmitters typically synthesized?
A. In the cell body ribosomes
B. In the axon terminal
C. In the Golgi apparatus
D. In the dendritic spines
Answer: B
Rationale: Small-molecule neurotransmitters are usually synthesized at the axon terminal
from precursors using enzymes transported from the cell body.
4. Where are neuropeptides primarily synthesized?
A. In the synaptic cleft
B. In the axon terminal cytoplasm
C. In the nodes of Ranvier
D. In the cell body (soma)
Answer: D
Rationale: Neuropeptides are synthesized in the cell body because they require protein
synthesis machinery like the endoplasmic reticulum and Golgi.
5. The influx of which ion into the presynaptic terminal triggers
neurotransmitter release?
A. Potassium (K+)
B. Sodium (Na+)
C. Calcium (Ca2+)
D. Chloride (Cl-)
Answer: C
Rationale: Action potentials reaching the terminal open voltage-gated calcium channels;
the resulting Ca2+ influx triggers vesicle fusion.
, 6. Which SNARE protein is specifically located on the vesicle membrane?
A. Synaptobrevin
B. Syntaxin
C. SNAP-25
D. Synaptotagmin
Answer: A
Rationale: Synaptobrevin is the v-SNARE (vesicle SNARE), while syntaxin and SNAP-25 are
t-SNAREs (target SNAREs) on the plasma membrane.
7. Which protein acts as the primary calcium sensor during synaptic vesicle
exocytosis?
A. Calmodulin
B. Synaptotagmin
C. Clathrin
D. Dynamin
Answer: B
Rationale: Synaptotagmin binds calcium ions and triggers the final fusion step of the
vesicle with the presynaptic membrane.
8. Which process allows for the recovery of the synaptic vesicle membrane after
exocytosis?
A. Apoptosis
B. Phagocytosis
C. Endocytosis
D. Pinocytosis
Answer: C
Rationale: Endocytosis is the process by which the vesicle membrane is retrieved and
recycled from the presynaptic plasma membrane.
Neurotransmitters Exam 2026/2027 UPDATE UPDATED
ACTUAL Questions and CORRECT Answers
1. Which of the following is a key characteristic of electrical synapses?
A. They utilize neurotransmitters to bridge the gap
B. They allow for nearly instantaneous signal transmission
C. They are wider than chemical synapses
D. They involve a significant synaptic delay
Answer: B
Rationale: Electrical synapses use gap junctions to allow direct ionic current flow,
resulting in high speed and minimal delay.
2. What is the approximate width of the synaptic cleft in a chemical synapse?
A. 1-2 nm
B. 5-10 nm
C. 20-50 nm
D. 100-200 nm
Answer: C
Rationale: The synaptic cleft in chemical synapses is typically between 20 and 50
nanometers wide.
,3. Where are small-molecule neurotransmitters typically synthesized?
A. In the cell body ribosomes
B. In the axon terminal
C. In the Golgi apparatus
D. In the dendritic spines
Answer: B
Rationale: Small-molecule neurotransmitters are usually synthesized at the axon terminal
from precursors using enzymes transported from the cell body.
4. Where are neuropeptides primarily synthesized?
A. In the synaptic cleft
B. In the axon terminal cytoplasm
C. In the nodes of Ranvier
D. In the cell body (soma)
Answer: D
Rationale: Neuropeptides are synthesized in the cell body because they require protein
synthesis machinery like the endoplasmic reticulum and Golgi.
5. The influx of which ion into the presynaptic terminal triggers
neurotransmitter release?
A. Potassium (K+)
B. Sodium (Na+)
C. Calcium (Ca2+)
D. Chloride (Cl-)
Answer: C
Rationale: Action potentials reaching the terminal open voltage-gated calcium channels;
the resulting Ca2+ influx triggers vesicle fusion.
, 6. Which SNARE protein is specifically located on the vesicle membrane?
A. Synaptobrevin
B. Syntaxin
C. SNAP-25
D. Synaptotagmin
Answer: A
Rationale: Synaptobrevin is the v-SNARE (vesicle SNARE), while syntaxin and SNAP-25 are
t-SNAREs (target SNAREs) on the plasma membrane.
7. Which protein acts as the primary calcium sensor during synaptic vesicle
exocytosis?
A. Calmodulin
B. Synaptotagmin
C. Clathrin
D. Dynamin
Answer: B
Rationale: Synaptotagmin binds calcium ions and triggers the final fusion step of the
vesicle with the presynaptic membrane.
8. Which process allows for the recovery of the synaptic vesicle membrane after
exocytosis?
A. Apoptosis
B. Phagocytosis
C. Endocytosis
D. Pinocytosis
Answer: C
Rationale: Endocytosis is the process by which the vesicle membrane is retrieved and
recycled from the presynaptic plasma membrane.
