BIOL1003 Lecture Notes - Lecture 9: Sensory Neuron, Neural Adaptation, Thermoreceptor
19 May 2018
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Department
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Professor
Discuss specificity of receptors and explain adaptation
Receptors sensitive to different stimuli
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Specificity of receptors
If sensory receptor is stimulated continuously, receptor may eventually turn off, ceasing to
respond or respond weakly
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Decrease in transmission of impulses is known as sensory adaptation and occurs without a
change in stimulus strength
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Some receptors adapt more rapidly than others
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Temperature receptors - hot and cold water bath
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Branching ends of dendrites of certain sensory neurons and found in almost every
tissue of body
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Adapt to stimuli only SLIGHTLY, so not everything is perceived as painful
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Pain receptors
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Examples
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Adaptation
9a)
Sunday, 14 May 2017
10:57 AM
9. The Senses Page 1
Describe sensory receptors and outline the different sensory
receptors of the skin
Screen clipping taken: 14/05/2017 11:26 PM
Sensory receptors - sensory nerve endings or specialised cells capable of responding to stimuli
by developing action potentials
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Mechanoreceptors
Respond to mechanical stimuli such as bending or stretching of
receptors
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Chemoreceptors
Respond to chemicals such as odour molecules
Photoreceptors
Respond to light
thermoreceptors
Respond to temperature changes
Nociceptors
Respond to stimuli that result in the sensation of pain
Mechanoreceptors - touch and pressure
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Thermoreceptors - temp changes
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chemoreceptors
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Sensory receptors of the skin
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9b)
Sunday, 14 May 2017
9:30 PM
9. The Senses Page 2
Define special sense organs
Eye
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Ear
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Nose
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Tongue
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Senses - smell, taste, sight, hearing, balance
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Associated with very specialised, localised sensory receptors
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Smell and taste - initiated by the interaction of light with sensory receptors
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Hearing and balance - function in response to interaction of mechanical stimuli with sensory
receptors
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Hearing - in response to soundwaves, balance occurs in response to gravity of motion
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9c)
Sunday, 14 May 2017
9:31 PM
9. The Senses Page 3
Document Summary
If sensory receptor is stimulated continuously, receptor may eventually turn off, ceasing to respond or respond weakly. Decrease in transmission of impulses is known as sensory adaptation and occurs without a change in stimulus strength. Temperature receptors - hot and cold water bath. Branching ends of dendrites of certain sensory neurons and found in almost every tissue of body. Adapt to stimuli only slightly, so not everything is perceived as painful: the senses page 1. Describe sensory receptors and outline the different sensory receptors of the skin. Sensory receptors - sensory nerve endings or specialised cells capable of responding to stimuli by developing action potentials. Mechanoreceptors respond to mechanical stimuli such as bending or stretching of receptors. Respond to stimuli that result in the sensation of pain. Thermoreceptors - temp changes chemoreceptors: the senses page 2. Smell and taste - initiated by the interaction of light with sensory receptors.
