Answer to Question #198599 in Biology for hen

Question

The sensory neurone was stimulated electrically and the FURA-2 fluoresence in the synaptic bulb was measured. At the same time an electrode recorded the membrane potential in a postsynaptic neurone. The results of this study are shown below:

 

Strengths of electrical

stimulation  Low Medium High

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FURA-2 fluoresence in

synaptic bulb Low Medium High

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Highest membrane potential

in postsynaptic neurone (mV) -60 +40 +40

The intesity of FURA-2 fluorescence is proportional to the concentration of Ca²⁺ ions.

The scientists concluded that changes in the concentration of Ca²⁺ ions in the presynaptic neurone caused an action potential in the post synaptic neurone.

Evaluate and explain the scientists' conclusion.

Answer 1

An increase in the intensity of electrical stimuli was associated with the increase in the FURA-2 fluorescence. The observation demonstrates that electrical stimuli increase calcium concentration in the presynaptic neuron. Next, increase in the intensity of stimuli was associated with depolarisation of the postsynaptic neuron. From here, it can be concluded that the production of action potential in the postsynaptic neuron is associated and might be caused by increased concentration of calcium in the presynaptic neuron.