U4 Sensory System Introduction UPDATED ACTUAL
Questions and CORRECT Answers
Afferent Division somatic sensory, visceral sensory, special sensory
Somatic Sensory Gen. senses: touch, pressure, temp; external/conscious
Visceral Sensory glucose, osmolarity, O2, BP; internal/unconscious
Special Sensory taste, smell, vision, hearing, equilibrium; external/conscious -> cerebral cortex
Sensory Receptors Function convert chemical/physical stimulus into nerve signal = APs -> language of CNS
Sensation awareness of stimulus (signal must reach CNS)
Sensory Receptors Specialized receptor endings, detect stimulus on neuron; or receptor cell
communicates with sensory neuron
Sense Organs Neurons, receptor cells + other tissues that enhance response; Ex: eye, ear
Sensory Receptor Classification: Thermoreceptors Temperature: Cold, Heat
Sensory Receptor Classification: Photoreceptors Photons of light
Sensory Receptor Classification: Nociceptors Pain receptors (specialized chemoreceptors)
Sensory Receptor Classification: Chemoreceptors Chemicals (glucose, ions, etc.)
Sensory Receptor Classification: Mechanoreceptors Physical Deformation
Sensory Receptor Classification: Proprioceptors Specialized mechanoreceptors -> body position + movement
Modalities of Sensation Touch, pain, sound, etc.
Each receptor is responsive to: only one type of stimulus energy, specificity is key property of receptor,
underlies coding mechanism (labeled line code)
Receptor Excitation: Mechanical Deformation Stretches plasma membrane + pulls open ion channels
Receptor Excitation: Application of chemicals Opens ion channels (ligand-gated)
Receptor Excitation: Change in Temperature alters membrane permeability
Receptor Excitation: Electromagnetic radiation Changes membrane characteristics
How is stimulus transformed into an electrical Stimulus opens ion channels on sensory neuron or sensory cell, which
response? produces a graded potential called a receptor potential
Receptor Potential Defined as membrane potential of the receptor (local potential)
Questions and CORRECT Answers
Afferent Division somatic sensory, visceral sensory, special sensory
Somatic Sensory Gen. senses: touch, pressure, temp; external/conscious
Visceral Sensory glucose, osmolarity, O2, BP; internal/unconscious
Special Sensory taste, smell, vision, hearing, equilibrium; external/conscious -> cerebral cortex
Sensory Receptors Function convert chemical/physical stimulus into nerve signal = APs -> language of CNS
Sensation awareness of stimulus (signal must reach CNS)
Sensory Receptors Specialized receptor endings, detect stimulus on neuron; or receptor cell
communicates with sensory neuron
Sense Organs Neurons, receptor cells + other tissues that enhance response; Ex: eye, ear
Sensory Receptor Classification: Thermoreceptors Temperature: Cold, Heat
Sensory Receptor Classification: Photoreceptors Photons of light
Sensory Receptor Classification: Nociceptors Pain receptors (specialized chemoreceptors)
Sensory Receptor Classification: Chemoreceptors Chemicals (glucose, ions, etc.)
Sensory Receptor Classification: Mechanoreceptors Physical Deformation
Sensory Receptor Classification: Proprioceptors Specialized mechanoreceptors -> body position + movement
Modalities of Sensation Touch, pain, sound, etc.
Each receptor is responsive to: only one type of stimulus energy, specificity is key property of receptor,
underlies coding mechanism (labeled line code)
Receptor Excitation: Mechanical Deformation Stretches plasma membrane + pulls open ion channels
Receptor Excitation: Application of chemicals Opens ion channels (ligand-gated)
Receptor Excitation: Change in Temperature alters membrane permeability
Receptor Excitation: Electromagnetic radiation Changes membrane characteristics
How is stimulus transformed into an electrical Stimulus opens ion channels on sensory neuron or sensory cell, which
response? produces a graded potential called a receptor potential
Receptor Potential Defined as membrane potential of the receptor (local potential)
