Receptor potential

Definition

Receptor potential is a graded electrical response generated in sensory receptor cells when they are stimulated by an external stimulus. It is the initial step in the process of sensory transduction, converting physical stimuli into electrical signals.

5 Must Know Facts For Your Next Test

1. Receptor potentials are graded, meaning their amplitude varies with the intensity of the stimulus.
2. They occur at the site of sensory receptor cells, such as in photoreceptors, mechanoreceptors, and chemoreceptors.
3. Unlike action potentials, receptor potentials do not follow an all-or-nothing principle; instead, they vary in magnitude.
4. If the receptor potential is strong enough and reaches a certain threshold, it can trigger an action potential in a sensory neuron.
5. Receptor potentials can lead to the release of neurotransmitters if they reach synaptic terminals.

Review Questions

• What characteristic differentiates receptor potentials from action potentials?
• Where do receptor potentials typically occur within sensory systems?
• How does a receptor potential contribute to the generation of an action potential?

Related terms

Sensory Transduction: The process by which sensory stimuli are converted into electrical signals in the nervous system.

Action Potential: A rapid rise and fall in membrane potential that propagates along neurons to transmit information.

Sensory Receptor: A specialized cell or structure that detects specific types of stimuli from the environment and initiates sensory transduction.