Intracellular transport in dependent on the cytoskeleton, which is compromised of three main structural elements including microtubules (long grey tubes in figure), actin (not pictured), and intermediate filaments (not pictured). Microtubules are the main "skeleton" creating the overall shape of the cell along with providing directional transport highways for movement within the cell. Movement is generated by motor proteins such as kinesins and dynein that convert chemical energy (ATP) into kinetic energy. Finally, there is the cargo that moves from the site of synthesis in the cell body, i.e., the Golgi apparatus, outwards into the axon and dendrites. These cargo include proteins and lipids needed to build the neuron and support synaptic function i.e., information storage and transmission. Cargo can also move from distal portions of the neuron back to the cell body where cellular material can be degraded and/or recycled.
