chapter 50: sensory and motor mechanisms Flashcards
What are the four basic functions in sensory pathways?
- sensory reception
- transduction
- transmission
- integration
What is the role of sensory reception?
- sensations begin with sensory reception, detection of stimuli by sensory receptors
- there are neuronal receptors: afferent neuron
- there are non-neuronal receptors: receptor regulates afferent neuron
What is the role of sensory transduction?
- its the conversion of stimulus energy into change in sensory receptor membrane potential.
- the change in membrane potential is called receptor potential
What is the role of transmission?
- transducing the energy in a stimulus into a receptor potential initiates transmission of action potentials
- sensory neurons produce action potentials
- if receptor is a neuron, larger receptor potential results in more frequent action potentials.
- if receptor isnt a neuron, larger receptor potential causes more neurotransmitters to be released
What is the perception?
brains construction of stimuli
the brain distinguishes stimuli from different receptors based on the are in the brain where action potential arrives
What is amplification?
strengthing of a sensory signal during transduction
What is sensory adaptation?
decrease in responsiveness to continued stimulation
What are the different kinds of sensory receptors?
- mechanoreceptors
- chemoreceptors
- electromagnetic receptors
- thermoreceptors
- pain receptors
What are mechanoreceptors?
- they sense physical deformation caused by forms of mechanical energy
- responses to touch, stretch, motion, pressure and sound relies on mechanoreceptors
- found in the dendrites
What are chemoreceptors?
-transmit information about the total solute concentration of a solution
- when stimulus molecule binds to chemoreceptor, it becomes more or less permeable to ions
What are electromagnetic receptors?
- detect electromagnetic energy such as light, electricty and magnetism
- animals use this to migrate using earths magnetic field
What are thermoreceptors?
- respond to heat or cold and help regulate temperature by signalling both surface and body core temperatures
- some snakes use this to detect infrared radiation emitted by warm prey
What are pain receptors?
- pain receptors or nociceptors detect stimuli that reflect harmful conditions
- they respond to excess heat, pressure, chemicals
Why are mechanoreceptors responsible for hearing and equilibirum?
- mechanoreceptors located in organs called statocysts, where they detect movement of granules called statoliths
- some arthropods sense sounds with body haurs that vibrate
What is the cochlea?
has two large structure found in the ear