★
What is the specialized cell that transmits nerve impulses throughout the body?
Neuron
What is the state of a neuron when it is ready to send a signal?
Resting potential
What is the positively charged particle that rushes into a neuron during depolarization?
Sodium (Na⁺)
What is the positively charged particle that exits a neuron during repolarization?
Potassium (K⁺)
What are the always-open “channels” in the neuronal membrane that allow ions to pass slowly?
Leak channels
What is the minimum stimulus required to trigger an action potential?
Threshold
What is the rapid electrical signal that travels along the axon?
Nerve Impulse or Action potential
What is the period when a neuron cannot immediately fire another signal?
Refractory period
What occurs when the inside of a neuron becomes temporarily more negative than at rest?
Hyperpolarization
At what membrane potential does the neuron return to its resting state after an action potential?
–70 mV
What type of neuron carries information from the sense organs to the brain/ spinal cord?
Sensory neuron
What type of neuron in the brain or spinal cord interprets signals?
Interneuron
What type of neuron carries signals from the brain or spinal cord to muscles or glands?
Motor neuron
What is the phase of an action potential when the inside of a neuron returns to a negative state?
Repolarization
What is the phase of an action potential when the inside of a neuron becomes positive?
Depolarization
What receptors in the eyes detect light and motion?
Photoreceptors
What receptors in the ears detect sound vibrations?
Hair cells
What is the muscle or gland that carries out a response to a signal?
Effector
What is any change in the environment detected by a receptor?
Stimulus
At what membrane potential does the neuron reach threshold to initiate an action potential?
–55 mV
What is the first function of the nervous system that gathers information from the body?
Sensory input
What is the function of the nervous system that executes the body’s response?
Motor output
What is the name of the specialized plasma membrane that surrounds the axon’s cytoplasm (axoplasm)?
Axolemma
What is the function of the nervous system that interprets information and decides on a response?
Integration
What is the pathway that carries signals from stimulus to response?
Stimulus → Receptor → Sensory Neuron → Interneuron → Motor Neuron → Effector → Response