Transcript Receptors - Southeast Missouri State University

Receptors
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Electrical signals produced by excitable cells
Neurons, muscle fibers
Potentials
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Action
Graded
Threshold
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Electrical signals produced by excitable cells
Types of Synapses
Excitatory and Inhibitory Post synaptic potentials
Neurotransmitters
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Neuromuscular junction-acetylcholine
Biogenic Amines-epinepherine, norepinepherine, serotonin, dopamine
Amino Acids
Peptides-endorphins, substance P
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Sensation and Perception
Sensory Modality
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Processing at the Receptor Level
---The process of sensation
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Stimulation
Transduction
Generation of nerve impulse
Integration
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Sensory input via receptors
Types of receptors:
1. free nerve endings
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Merkel disk
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Follicle receptor
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Itch receptor
2. encapsulated
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Meissner’s corpuscle
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Pacinian
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Ruffini
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Golgi tendon organ
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Muscle spindles
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Kinesthetic receptors
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Sensory input via receptors
Types of receptors:
3. Separate cells
 Hair cells
 Gustatory receptors
 Photoreceptors
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Types of Receptors
Stimulus:
 Thermoreceptors
 Chemoreceptors
 Photoreceptors
 Mechanoreceptors
 Nociceptors
Location:
Exteroreceptors
Interoreceptors
Proprioreceptors
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Adaptation
Adaptation occurs when sensory receptors are subjected to an
unchanging stimulus
Exception: Nociceptors and Proprioceptors
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Checkpoint questions:
12.25 How are graded potentials and the action potential threshold related?
12.26 What is the all or none principle? Are graded potentials all-or-none?
12.36 Explain the effects of excitatory and inhibitory postsynaptic potentials on
the postsynaptic neuron.
15.2 Distinguish between general and special senses.
15.4 What four events must occur for a sensation to occur?
15.5 What is transduction?
15.7 What is adaptation? How does it occur?
15.10 Why do we need pain receptors? How are they activated?
15.13 What is the function of joint kinesthetic receptors?
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