BIOL 2301 Chapter 17 Lecture Notes PDF

Chapter 17: General Sensations Receptors Stimuli and Sensations Receptors as Transducers Receptive Field Tonic and Phasic Receptors, Adaptation Receptor Distribution * Somatic sensory receptors * Visceral sensory receptors * Special senses Brief outlines only. For det...

Chapter 17: General Sensations Receptors Stimuli and Sensations Receptors as Transducers Receptive Field Tonic and Phasic Receptors, Adaptation Receptor Distribution * Somatic sensory receptors * Visceral sensory receptors * Special senses Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Stimulus origin: Exteroceptors Interoceptors Proprioceptors Modality of stimulus: Chemoreceptors Thermoreceptors Photoreceptors Mechanoereceptors Baroreceptors Nociceptors Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat General Senses: Tactile receptors Capsulated Sensory receptors: Meissner’s corpuscles or Tactile corpuscles Pacinian corpuscles or Lamellated corpuscles Ruffini corpuscle or Ruffini end organ Krause end bulb or Bulbous corpuscle Un-encapsulated Sensory receptors: Free nerve endings Root hair plexus Merkel discs or Tactile discs Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Pacinian or Lamellated Corpuscles Location Structure They are large sized mechanoreceptors Detect deep pressure and high frequency vibrations Rapidly or fast adapting receptors Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Meissner’s corpuscles or Tactile Corpuscles Location Structure Detect fine (light) touch or light pressure. Rapidly or fast adapting receptors. Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Ruffini’s corpuscles or Ruffini’s end organs Location Structure Detect stretch Slow adapting receptors. Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Krause’s end bulbs or Bulbous corpuscles Location Mechanoreceptors (sensitive to light pressure) Also, thermoreceptors sensitive to cold Slow adapting receptors. Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Merkel discs or Tactile discs or Merkel Nerve Endings Location Structure Fine touch felt as pressure; detect shapes and edges Slow adapting receptors. Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Free nerve endings Location Structure Multiple functions: Pain, Temperature, Displacement Slow adapting: Pain and cold receptors Fast adapting receptors: Warm receptors Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Hair root plexus Location Detect hair movement Fast adapting receptors Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Two-point discrimination Spatial acuity, ability to distinguish two points as two ‘separate’ points Density of touch or tactile receptors determines the degree of sensitivity Sensitivity of fingers vs. back of torso Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Adaptation of Receptors Fast or rapidly adapting receptors (phasic receptors Slow adapting receptors (tonic receptors) Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Fast adapting receptors: Pacinian corpuscles and Meissner's corpuscles. Warm receptors Hair root plexus Slow adapting receptors: Ruffini's corpuscles or Ruffini’s end organs Merkel discs or Tactile discs Krause’s end bulb or Bulbous corpuscles. Nociceptors Cold receptors Others: Olfactory receptors Gustatory receptors Photoreceptors Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Proprioceptors Sense the body’s position in space and body’s movements through space Muscle Spindle Golgi Tendon Organs Pacinian corpuscles and Ruffini’s end organs Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Muscle Spindle (i) Extrafusal muscle fibers, alpha motor fibers (ii) Intrafusal fibers, gamma motor fibers, Type Ia sensory nerve fibers (iii) Muscle spindle protects the muscle from overextension (iv) alpha-gamma motor nerve fiber interaction Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat Golgi Tendon Organs Located within the muscle tendon Sensory fibers activated when muscle contracts Golgi tendon organs protect the muscle tendons Brief outlines only. For details, please refer to the BIOL 2301 Lecture Text on Top Hat