synapse helps in information processing by combining the effects of all impulses received. what do these lines mean?

Dear Soumya,

Thank you for asking!

First, I will make it clear that what synapse means.
Synapse is a juction where two neurons meet and transfer the information in only one direction.
During the transmission of impulse, Pre-synaptic neuron collects the cumulative impulses and transfer it to the region of synaptic cleft. The information are running through the neurons in the form of action potential, The action potential is processed at synapse.

Hope the answer of the question.