Okay, so this lecture, we are going to talk about the morphology of neuronal cell. Before we are getting into this topic today, we want to mention two concepts. One is reductionism, and the other is hypothesis. What is the reductionism? Reductionism is we want to study an issue and we divide this issue into several smaller compartments. For example, physiology, if we want to study the physiological function of our whole body, first of all, we want to divide our body into organs like systems and organs. Like digestion system or the system we use to do our metabolism. And then in this system, we further divide this system into organs. For example, in the digestion system, we have stomach, and we have our tubular structure. And then in these organs, we further divide our organs into smaller pieces, for example, our cells in our stomach. Under the cell, we have different subcellular compartment like nucleus and reticular Golgi and other compartments. And then in these cellular or subcellular compartments that we can further divide into proteins, molecules, nucleic acid. So this approach called reductionism. And then all our modern science follow this reductionism for a long time, including mathematics, physics, chemistry, and of course, biology. And what are these rules? It's a good way or not to study more than science, it's still adorable. So this is a picture, a cover image of international journal of kidney and showing several scientists trying to study the morphology or the function of elephant. And it depends on where to look and where the scientist is. They report different morphology of elephant. So the one sitting on the top of elephant, touching the elephant's ears, says elephants is like a fan. And then the one standing on the side of the elephant, touching the trunk of elephant, it says the elephant is like a wall. And then the one holding his tail said that the elephant is actually a rope. That's reflect respect of the problem that produced by reductionism, that we cannot see the whole picture. So the other research is so detailed and so narrow so that we can only see a certain perspective of our problem or our issue and we cannot study the whole picture. And then because we are following the reductionism to study the issue in question, our scientific question, then we needed to have hypothesis. A hypothesis is a testable statement that we can use either observation or experiment to test whether this statement is true or not.