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Answer:
Surface Area to Volume Ratios: Notice that as a cell increases in size, its surface area-to-volume ratio decreases. When there is insufficient surface area to support a cell's increasing volume, a cell will either divide or die.
Answer:
A neuron receives stimuli consisting of the response of thousands of neurons. Synapse is the signals entering the neuron via junctions called. The role of the synapses are to modulate the signal strength and determine the input signal is either excitatory, promoting the neuron to fire, or inhibitory, tending to prevent the neuron from firing.
At the axon hillock the neuron integrates the inputs and if this total is excitatory then the neuron fires. Although this brief description leaves out much of the complexity, it is still remarkable that out of this web of electrochemical firing units, emerges our very conscious.