Senses Flashcards
(122 cards)
Depends on sensory receptors.
Sense receptors
Respond to various stimuli. What is this?
What triggers an impulse in a receptor?
What travels to cerebral cortex are processed and interpreted?
- Sense receptors
- Stimulus
- Action potentials
Receptors are widely distributed in the body; pain, touch, pressure, proprioception
General senses
Receptors are localized in a particular area; smell, hearing, sight
Special senses
Stimulus of this sense receptor changes in chemical concentration of substances. What is this? What is an example of this? (2)
Chemoreceptors
- taste and smell
Stimulus of this sense receptors cause changes in pressure or movement in fluids. Examples are proprioceptors in joints, receptors for hearing and equilibrium.
Mechanoreceptors
Stimulus of this sense receptor causes tissue damage. Example of this are pain receptors
Nociceptors
Stimulus of these sense receptors causes changes in temperature. Examples are heat and cold.
Thermoreceptors
Stimulus of these sense receptors are light energy and an example is vision.
Photoreceptors
Steps involved in sensory perception:
- Stimulus
- Receptor detects the stimulus and creates an action potential
- Action potential (impulse) is conducted to the CNS
- Within the CNS, the impulse is translated into information
- Information is interpreted in the CNS into an awareness or perception of the stimulus
A decreased sensitivity to a continued stimulus. Triggers impulses only if strength of stimulus is increased. Some sense receptors are most sensitive to changes in stimulus. They become tolerant to continuous stimuli of the same strength.
Sensory adaptation
Found throughout the body. Associated with visceral organs, skin, muscles, joints. Include touch, pressure, proprioception, temperature, and pain.
General senses (Somatic Senses)
Receptors for touch and pressure. Sensitive to forces that deform or displace tissues. Widely distributed in the skin.
Mechanoreceptors
Mechanoreceptors involved in touch and pressure. Have no connective tissue covering. Interspersed in epithelial tissue. Sens objects that are in continuous contact with the skin (e.g. clothing)
Free nerve endings
Mechanoreceptors involved in touch and pressure. Located in dermal papillae (just beneath epidermis). Sense light discriminative touch stimuli
Meissner’s corpuscles
Mechanoreceptors involved in touch and pressure. Located in deeper dermis and subcutaneous tissues, tendons, ligaments, because several layers of connective tissue surrounded the nerve endings. Stimulated by heavy pressure.
Pacinian corpuscles (lamellated corpuscles)
Sense of position or orientation. Allows an individual to sense the location and rate of movement of on body pat relative to another.
Proprioception
Important Mechanoreceptors for proprioception. Location is junction of a tendon with a muscle. Muscles spindles (located in skeletal muscle).
Golgi tendon organs
Located immediately under skin. Temperature receptors help the human being avoid damage to the skin from excessive heat or cold. Widely distributed throughout the body:
- Most numerous: Lips
- Least numerous: Broad surfaces of trunk
Thermoreceptors
Thermoreceptors has up to how many times more cold receptors in a given areas than heat receptors?
Thermoreceptors extremes in temperature simulate pain receptors is below how many degrees Celsius? Pain receptors produce a freezing sensation.
- 10 times
- Below 10 degrees Celsius
As temperature increases above how many degrees Celsius and Fahrenheit cause pain impulse to cease and cold receptors behind to be stimulated?
10 degrees Celsius and 50F
At temperatures about how many degrees Celsius and Fahrenheit does heat receptors begin to be stimulated and cold receptors fade out?
25 degrees C and 77F
As temperatures approach how many degrees Celsius and Fahrenheit does heat receptors fade out and pain receptors are stimulated; producing a burning sensation?
45 degrees Celsius and 113 F
Extreme cold and extreme heat feels almost the same. Both are painful and pain receptors are being stimulated. What is exhibited by thermoreceptors causing thermoreceptors are strongly stimulated by abrupt changes in temperature. Then fade after a few seconds or minutes; for example, a heating pad no longer feels warm?
Sensory adaptation