Generally speaking, the main function of space cultured cells is to provide a completely different growth environment from the earth, which is well reflected in the answers of the above students. I won't be wordy. I mainly talk about the significance of gravity in cell culture. At present, there are two kinds of cells cultured in the laboratory, one is suspension cells and the other is adherent cells (I specialize in it). Adherent cells attach to Petri dishes by gravity, including most physiological cell types, such as nerve cells, muscle cells, epithelial cells and so on. And pathological cell models, such as cancer cells and neurodegenerative cells. Now, the three-dimensional cell model has developed from monolayer adherent cells. Therefore, our understanding of cells under laboratory conditions is basically based on gravity, which is completely ignored. Ignoring doesn't mean unimportant, just as we often ignore the existence of air. Under the action of gravity, the whole growth morphology of cells will change, especially the microtubule tissue. Although most existing cells have a three-dimensional structure, the real shape is like fried eggs, with a bulge in the middle of the nucleus and slowly hanging down around it. This is obviously influenced by gravity. Without the influence of gravity, will the microtubule tissue, which directly determines the shape of cells, stretch like this, or will it stretch freely in all directions like a sea urchin shell, up and down, left and right? Then, the morphological changes of a single cell will inevitably affect the morphology of the whole tissue, organs and even biological individuals. In addition, from the perspective of human development, we all complete our development in a gravitational environment. Although gravity may not affect the signal pathway in the development process, without the guidance of gravity, can the key proteins of development, such as growth factors, be transmitted along a certain gradient, so that cells can gradually develop into the existing human appearance? Or is the transmission of the key protein between cells completely disoriented, leading to the failure of development or the development of superhuman beings with superhuman powers (big brain holes)? Before entering the space age, this is a problem that mankind must face.