Term
| Name and describe the two different pathways of the afferent division |
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Definition
| 1. Visceral afferent pathway- carries information from the inner organs (heart, kidneys, upper digestive tract, etc.). 2. Somatic afferent pathway-either somatic sensation (skin) or proprioceptor (muscles, joints, skin); special senses (vision, hearing, taste, smell, balance.) |
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Term
| Differentiate between sensation and perception. |
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Definition
| Sensation is the conscious awareness of changes in the internal and external environment. Perception is the conscious interpretation of those stimuli. |
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Term
| Where are sensory receptors located? |
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Definition
| The sensory receptors are structures at the peripheral endings of afferent neurons |
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Term
Name the 6 different types of sensory receptors discussed in class.
What is the function of each? |
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Definition
| 1. Photoreceptors (light, photons). 2. Mechanoreceptors (touch, pressure, vibration, stretch, itch). 3. Thermoreceptors ( fluctuations in temperature). 4. Osmoreceptor (solute concentrations). 5. Chemoreceptors (specific chemicals..smell, taste, O2, CO2). 6. Nociceptor (pain receptor). |
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Term
| What takes place once a sensory receptor is stimulated? |
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Definition
| The stimulus alters membrane permeability of the receptor, which leads to an influx of ions. This produces a receptor (generator) potential. This is just another graded potential. The magnitude of receptor potential indicates stimulus intensity |
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Term
| How is the intensity of a stimulus determined? |
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Definition
| ? 1. Determined by frequency of action potential; degree of receptor potential; the greater the receptor potential, the more frequent action potential. 2. Number of receptors activated; area of stimulation (think about face and back of legs). |
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Term
| Name the two classes of adaptation |
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Definition
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Term
| What is the speed of adaptation of each? |
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Definition
| 1. Tonic (slow) receptors include chemoreceptors that respond to chemical levels in the blood; pain receptors and proprioceptors do not exhibit adaptation. 2. Phasic (fast) receptors adapt rapidly to pressure, touch, and smell; Pacinian corpuscle (mechanoreceptors) detect pressure and vibrations in the skin. |
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Term
| Can proprioceptors adapt? |
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Definition
| No, they do not exhibit adaptation. |
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Term
| Can smell chemoreceptors adapt? |
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Definition
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