LESSON 18: The nerve impulse Flashcards
What is the primary function of membrane transport in neurons?
To facilitate the movement of ions and molecules across the neuronal membrane for nerve impulse conduction.
True or False: The sodium-potassium pump moves sodium ions into the cell and potassium ions out of the cell.
False
Fill in the blank: The __________ potential is the electrical charge difference across the neuronal membrane at rest.
resting
What type of transport mechanism is primarily responsible for the rapid depolarization phase of the action potential?
Voltage-gated sodium channels
Multiple Choice: Which ion is primarily responsible for repolarization during an action potential?
Potassium (K+)
What is meant by ‘membrane permeability’ in the context of nerve impulses?
It refers to how easily ions can pass through the neuronal membrane.
True or False: Action potentials can travel backward along the axon due to the refractory period.
False
Fill in the blank: During the absolute refractory period, a neuron cannot generate another __________.
action potential
What role do calcium ions play in neurotransmitter release?
Calcium ions trigger the fusion of neurotransmitter-containing vesicles with the presynaptic membrane.
Multiple Choice: Which of the following is a type of passive transport?
Facilitated diffusion
What is the main purpose of the sodium-potassium pump?
To maintain the resting membrane potential by moving 3 Na+ out and 2 K+ into the cell.
True or False: Hyperpolarization makes a neuron more likely to fire an action potential.
False
Fill in the blank: __________ channels open in response to changes in membrane potential.
Voltage-gated
What is the significance of the threshold potential in action potential generation?
It is the critical level of depolarization that must be reached for an action potential to occur.
Multiple Choice: Which process describes the movement of neurotransmitters back into the presynaptic neuron?
Reuptake
What is the difference between active and passive transport in neuronal membranes?
Active transport requires energy to move ions against their concentration gradient, while passive transport does not.
True or False: Myelination increases the speed of action potential conduction.
True
Fill in the blank: The __________ is the part of the neuron that receives signals.
dendrite
What is the role of neurotransmitters in synaptic transmission?
They transmit signals across the synaptic cleft to the postsynaptic neuron.
Multiple Choice: Which type of ion channel opens in response to neurotransmitter binding?
Ligand-gated ion channels
What causes the ‘all-or-nothing’ response in action potentials?
The action potential either occurs fully or not at all once the threshold is reached.
True or False: The conduction of nerve impulses is slower in unmyelinated axons compared to myelinated axons.
True
Fill in the blank: The period during which a neuron is less responsive to stimuli after an action potential is called the __________ period.
refractory
What is a synapse?
The junction between two neurons where neurotransmission occurs.
