Adequate stimulus

The adequate stimulus is a property of a sensory receptor that determines the type of energy to which a sensory receptor responds with the initiation of sensory transduction. Sensory receptor are specialized to respond to certain types of stimuli. The adequate stimulus is the amount and type of energy required to stimulate a specific sensory organ.
Many of the sensory stimuli are categorized by the mechanics by which they are able to function and their purpose. Sensory receptors that are present within the body typically are made to respond to a single stimulus. Sensory receptors are present all throughout the body, and they take a certain amount of a stimulus to trigger these receptors. The use of these sensory receptors allows the brain to interpret the signals to the body which allow a person to respond to the stimulus if the stimulus reaches a minimum threshold to signal the brain. The sensory receptors will activate the sensory transduction system which will in turn send an electrical or chemical stimulus to a cell, and the cell will then respond with electrical signals to the brain which were produced from action potentials. The minuscule signals, which result from the stimuli, enter the cells must be amplified and turned into an sufficient signal that will be sent to the brain.
A sensory receptor's adequate stimulus is determined by the signal transduction mechanisms and ion channels incorporated in the sensory receptor's plasma membrane. Adequate stimulus are often used in relation with sensory thresholds and absolute thresholds to describe the smallest amount of a stimulus needed to activate a feeling within the sensory organ.
Categorizations of receptors.
They are categorized through the stimuli to which they respond. Adequate stimulus are also often categorized based on their purpose and locations within the body. The following are the categorizations of receptors within the body:
Classes.
There are several different types of stimuli to which adequate stimuli respond. The following are examples of stimuli to which receptors may:
Sensory receptors.
Sensory receptors are the ends of nerves within the body that respond to stimuli. There are many different types of sensory receptors that each respond to stimuli that they are uniquely fitted to res Types of sensory receptors include the following: 
Classic examples of absolute threshold.
In 1962, Eugene Galanter, a psychologist, tested stimuli till people were able to feel them approximately 50% of the time, then used the following as examples of absolute threshold:
Through these conditions, Galanter was able to show that human's sensory organs are often more sensitive than originally thought.