Neurons MCQ Flashcards
Which of these statements about neuronal axons is CORRECT?
A Axons with a larger diameter have slower conduction velocity than those with a small
diameter
B Myelinated axons have voltage-gated sodium channels distributed evenly along their
length
C Unmyelinated axons have slower conduction velocity than myelinated axons
D Voltage-gated sodium channels are not concentrated at nodes of Ranvier
E Nodes of Ranvier are not present in myelinated axons
C
Which of these statements about neurotransmitters is INCORRECT?
A Amino acid neurotransmitters only activate ligand-gated ion channels
B Glycine is an amino acid neurotransmitter
C There are many neuropeptide neurotransmitters
D Noradrenaline is an amine neurotransmitter
E Serotonin (5-HT) is an amine neurotransmitter
A
Which of the following statements about neuronal dendrites is INCORRECT? The dendrites of neurons are
A where the majority of synapses are located
B where neurotransmitters are released by the neuron
C variable in length
D branched
E unmyelinated
B
You measure a current of 100 picoamperes (100 x 10-12 A) moving across a neuron’s membrane when you change the neuron’s membrane potential by 10 millivolts (10 x 10-3 V). Which of the following answers gives the resistance of the neuron’s membrane to current movement?
A 1 gigaohm (1 x 109 ohms)
B 100 megaohms (1 x 108 ohms)
C 100,000 ohms (1 x 105 ohms)
D 10 megaohms (1 x 107 ohms)
E 1 megaohm (1 x 106 ohms)
B
Which statement about long-term potentiation (LTP) of synaptic transmission is CORRECT?
A LTP is not seen in the hippocampus
B LTP does not require NMDA receptor activation, calcium ion influx or protein kinase
activation
C LTP only lasts for approximately thirty minutes
D LTP causes changes in postsynaptic NMDA receptor number and phosphorylation
E LTP requires summation of multiple synaptic inputs
E
Which of the following mechanisms is involved in clearance of released neurotransmitters from the synaptic cleft?
A re-uptake into surrounding glial cells by specific transporters
B slow breakdown by non-specific enzymes
C exocytosis of unchanged neurotransmitter
D re-uptake into the postsynaptic neuron by specific transporters
E simple diffusion in intracellular space
A
Which of the following statements about neurotransmitter synthesis is INCORRECT?
A Neuropeptide neurotransmitters are made in the cytoplasm of the synaptic terminal
B Amino acid neurotransmitters are made in the cytoplasm of the synaptic terminal
C Amine neurotransmitters are made in the cytoplasm of the synaptic terminal
D Neuropeptides are transported along the axon to the synaptic terminal in vesicles
E Neuropeptide neurotransmitters are made in the cell body Golgi apparatus
A
Which of these statements about neurotransmitters is INCORRECT?
A Serotonin (5-HT) is an amine neurotransmitter
B Some amine neurotransmitters activate G protein-coupled receptors
C Amino acid neurotransmitters only activate G protein-coupled receptors
D There are many neuropeptide neurotransmitters
E There are only a few amino acid neurotransmitters
C
Which of these statements about electrical and chemical neurotransmission is INCORRECT?
A Chemical neurotransmission is more reliable than electrical neurotransmission
B Chemical, but not electrical, neurotransmission is found in fetal brain tissue
C Electrical neurotransmission is fast compared to chemical neurotransmission
D Electrical neurotransmission is bi-directional, and chemical neurotransmission is one way
E Electrical neurotransmission can be modulated in many ways, and chemical neurotransmission has limited mechanisms for modulation
A
Which of these statements about neuronal axons is INCORRECT?
A Myelinated axons have voltage-gated sodium channels distributed evenly along their length
B Nodes of Ranvier are not present in unmyelinated axons
C Voltage-gated sodium channels are concentrated at nodes of Ranvier
D Axons with a larger diameter have faster conduction velocity than those with a small diameter
E Unmyelinated axons have slower conduction velocity than myelinated axons
A
Complete the following statement with the CORRECT ending. The dendrites of neurons are
A where action potentials are initiated
B where neurotransmitters are released onto other neurons
C uniform in length
D where neurotransmitters are received by neurons
E myelinated
D
Current (I), voltage (V), and resistance (R) are related to each other. What is the correct relationship and what is it called?
A R = V * I, Oersted’s Law
B V = I / R, Oersted’s Law
C V = I * R, Ohm’s Law
D I = R / V, Ohm’s Law
E I = V * R, Ohm’s Law
C
Which of the following statements about long-term potentiation of synaptic transmission is INCORRECT?
A It lasts for longer than 30 minutes
B It occurs in the hippocampus
C It involves changes in postsynaptic AMPA receptor number or phosphorylation
D It does not require summation of multiple synaptic inputs
E It requires NMDA receptor activation, calcium ion influx and protein kinase activation
D
Which of the following is NOT a mechanism for clearance of released neurotransmitters from the synaptic cleft?
A re-uptake into the post-synaptic neuron by specific transporters
B re-uptake into the synaptic terminal by specific transporters
C rapid breakdown by specific enzymes
D re-uptake into surrounding glial cells by specific transporters
E simple diffusion in extracellular space
A
Which of these statements about neurotransmitters is CORRECT?
A Serotonin (5-HT) is an amino acid neurotransmitter
B There are many amino acid neurotransmitters
C There are only a few neuropeptide neurotransmitters
D There are only a few amino acid neurotransmitters
E Amino acid neurotransmitters only activate ligand-gated ion channels
D
