Lecture 23: Sensory Receptors Flashcards
(12 cards)
What are visceral senses
Visceral means “deep down”…refers to senses that monitor your internal organs
What are special senses
Detected by highly specialized organs or structures.
eg. vision (eyes)
What does transduction mean
To convert or change from one form to another
What do tonic receptors do
They are continually active to reflect background level of stimulation
AP frequency changes when stimulus intensity changes
eg. proprioceptors (body position)
Slow adapting
What do Phasic receptors do
Normally silent (No APs)
Send APs with change but stop quickly
Fast adapting
What are chemoreceptors
specialized receptor cells with chemically-gated ion channels
They translate changes in chemical concentration to action potentials
eg. Oxygen CO2 and acid receptors
What are mechanoreceptors
nerve endings with mechanically-gated ion channels
Respond to physical forces that distort the plasma membrane
light touch receptors are typically phasic (fast-adapting), while proprioceptors and baroreceptors are tonic (slow-adapting)
What does Baroreception do
Detect pressure/stretch in vessels within the body
What do Nociceptors do
nerve endings that respond to noxious stimuli (harmful, painful) typically caused by tissue damage
have either temperature-gated, chemically-gated or mechanically-gated ion channels responding to extreme stimuli
What is the intensity of sensation determined by
The action potential frequency and number of neurons activated
What is the receptive field
The receptive field is the area encompassed by nerve endings for a single sensory neuron
What does the number and size of receptive fields determine
The number and size of receptive fields determines the localization accuracy of sensation
