Inside the brain :- Brain is one of the most important organ in the human body. Without brain a person could not able to survive.10% of your brain is fat. This is because many of your brain's nerve fibres are wrapped in a fatty sheath. This fatty sheath, called myelin, is vital as it insulates the nerves. This allows electrical impulses to travel quickly around your brain. Your brain is also swaddled in several layers of membranes called meninges. The fluid between these layers produces a water cushion that protects your brain if you knock or bump your head. Transporting of impulses :-The signal originates near the cell body of the pre-synaptic neuron. It travels via action potential down the axon to what is called the terminal button, which forms one part of the synapse. The terminal button contains neurotransmitters stored in vesicles. When the signal reaches the end of the axon, these vesicles fuse with the cell membrane and the neurotransmitters are dumped outside of the cell (a process called exocytosis) into the synapse.