Nerve Impulse (Leaving Cert Biology): Quizzes
📚Quizzes
Practise the questions
13 questions from this quiz
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Practise the questions
13 questions from this quiz
What causes a nerve impulse?
What causes a nerve impulse?
Movement of ions across neuron membrane
When a neuron is at rest, how is the axon charged?
When a neuron is at rest, how is the axon charged?
Inside negative, outside positive
What is the threshold?
What is the threshold?
Minimum stimulus to start nerve impulse
What does the All or Nothing Law state?
What does the All or Nothing Law state?
Impulse size unaffected by stimulus size
What determines the amount of pain felt?
What determines the amount of pain felt?
Number of neurons & impulse frequency
During a nerve impulse, how does the axon's charge change?
During a nerve impulse, how does the axon's charge change?
Inside becomes positive
What is the refractory period?
What is the refractory period?
Time for nerve to recover
How does myelin affect impulse speed?
How does myelin affect impulse speed?
Increases speed via nodes of Ranvier
How does neuron diameter affect impulse speed?
How does neuron diameter affect impulse speed?
Greater diameter = faster impulse
What is the synaptic cleft?
What is the synaptic cleft?
Gap between two neurons
Which are examples of neurotransmitters?
Which are examples of neurotransmitters?
Noradrenaline and dopamine
What happens to neurotransmitters after transmission?
What happens to neurotransmitters after transmission?
Broken down or reabsorbed
How do synapses control impulse direction?
How do synapses control impulse direction?
Ensure impulses travel one direction only