Receptors Flashcards
Sensory receptor cells
Sensory receptors are specialised to detect _______(changes in the environment) and transfer them producing an _______________response.
They are ________ _________________ transferring energy from one form to another.
Many work by opening and closing ion channels in the cell surface ___________of cells and producing a generator potential across the cells membrane.
The bigger the _________– the bigger the effect on the ion channel and the bigger the ___________ potential produced
Sensory receptors are specialised to detect stimuli (changes in the environment) and transfer them producing an electrochemical response.
They are energy transducers transferring energy from one form to another.
Many work by opening and closing ion channels in the cell surface membranes of cells and producing a generator potential across the cells membrane.
The bigger the stimulus – the bigger the effect on the ion channel and the bigger the generator potential produced
Different types of receptors – energy transducers.
Pacinian corpuscles are one type of ____________________- they detect __________stimuli e.g. ___________and vibrations.
They are found in the ____
Pacinian corpuscles are one type of mechanoreceptor - they detect mechanical stimuli e.g. pressure and vibrations.
They are found in the skin.
Pacinian corpuscles contain the end of a _________neurone
This sensory neurone ending is wrapped in loads of layers of ___________tissue called lamellae
Pacinian corpuscles contain the end of a sensory neurone
This sensory neurone ending is wrapped in loads of layers of connective tissue called lamellae
When a pacinian corpuscle is stimulated eg by a tap on the arm, the lamellae are ___________and press on the sensory nerve _________.
When a pacinian corpuscle is stimulated eg by a tap on the arm, the lamellae are deformed and press on the sensory nerve endings.
This causes the ___________neurone’s cell membrane to _______, deforming the stretch _____________sodium channels. The channels open which allows ___________ions to diffuse into the neurone
This causes the sensory neurone’s cell membrane to stretch, deforming the stretch mediated sodium channels. The channels open which allows sodium ions to diffuse into the neurone
This influx of sodium ions changes the ___________of the membrane, producing a _____________potential. The ________the pressure the more sodium ion channels open causing a _________generator potential.
If the generator potential reaches the ___________,it triggers ________``potential that passes along the neurone
This influx of sodium ions changes the potential of the membrane, producing a generator potential. The larger the pressure the more sodium ion channels open causing a bigger generator potential.
If the generator potential reaches the threshold ,it triggers action potential that passes along the neurone
What energy transfer takes place in a Pacinian corpuscle?
Mechanical/movement-> kinetic (ion movement) ->electrical potential (generator potential)
Which ion is moving into the sensory nerve ending?
Sodium ions Na +
What charge is on that ion?
Single positive +
What will happen to the charge on the inside of the sensory neurone ending when stimulated?
It will become more positive (less negative)
When ions concentration gradients build up on the outside of a cell – the gradient is called an electrochemical gradient – can you suggest why?
are more of the chemical –sodium ions outside the cell AND electro- because there is a charge gradient across the cell membrane with more positive (+) sodium ions outside the cell than inside.Chemical gradient because there
Stretch - Suggest how a person’s perception of touch might be affected by drugs that block stretch mediated sodium ion channels in cell membranes
Pressure from touch would normally deform the stretch mediated sodium ion channels in the pacinian corpuscles. However, by blocking sodium ion channels the drug would stop sodium ions from diffusing into the cell and generating an action potential. This would mean that the person wouldn’t be able to perceive that they were being touched.
