Special Senses Flashcards
(23 cards)
Mechanoreceptors
Sensory receptor that responds to mechanical pressures
Chemoreceptor
a sensory cell or organ responsive to chemical stimuli.
Thermoreceptors
Respond to change in temperature
Photoreceptors
Sensory receptor that is sensitive to light
Nociceptors
Sensory receptor that detects painful or injurious stimuli; also called pain receptor.
Three types of sensory receptors based on location
Cutaneous receptors
Viscerorecptors
Proprioceptors
associated with the skin and provide information about the external environment
Cutaneous receptors
associated with the viscera or organs. Provide information about the internal environment
Viscerorecptors
associated with joints, tendons, and other connective tissue. Provide information about the body position, movement, and the extent of stretch or force of muscular contractions
Proprioceptors
The simplest and most common sensory receptors are the
Free nerve endings
Increase the rate of action potential as skin cools
Cold receptors
Increase action potential as skin temperature increases
Warm receptors
Lies throughout basal layer of epidermis
Sensation of light touch and superficial pressure
Detect skin displacement of 1 mm
Merkel or tactile disks
Light bending of hair
Light touch
Hair follicle receptors
Complex receptors that resemble onion
Multiple layers of tissues surrounding a single dendrite
Deep cutaneous pressure and vibration
Joints positioning
Pacinian corpuscles
Lies throughout the dermal papillae
Two point discrimination
Numerous and close together in the tongue and fingertips
Less numerous and widely separated in other areas like the back
Meissner corpuscles
Fine touch
The ability to detect simultaneous stimulation of meissner corpuscles in two receptor fields by touching two points on the skin.
Two point discrimination
Located in dermis of the skin primarily the fingers
Responding to continuous touch or pressure
Ruffini end organs
Sense muscle stretch
Important to the control and tone of postural muscles
Muscle spindles
Sense muscle tendon stress
Cause inhibitory
Golgi tendon organs
Graded potential of sensory receptor
Receptor potential
Local change in the membrane potential that can vary from small to large
Graded potential
If a graded potential is large enough to reach threshold
Action potential is produced and probated toward CNS
