Researchers tried to explain how vesicular transport occurs in cells by attempting to assemble the transport components. They set up microtubular tracks along which vesicles could be transported, and they added vesicles and ATP (because they knew the transport process requires energy). Yet, when they put everything together, there was no movement or transport of vesicles. What were they missing?

According to my research on studies conducted by various biologists, I can say that based on the information provided within the question they seem to be missing Motor Proteins. These are motors that transport vesicles, thus converting chemical energy into work through the hydrolysis process that the ATP undergoes. Since they have the ATP and the Vesicles they would be able to accomplish the movement if they had the Motor Proteins.

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