Where does cellular biology fit into the big picture and how does it differ from microbiology, immunology, etc?
As a Cell Biologist I could wax lyrically for some time as to why it is central to the other sciences, but briefly, Cell Biology is focussed upon the cell as the functional element, inputs, outputs and functions. This means that the paradigms we are looking at should be applicable to all cells: eukaryotic (plants, animals, yeast) and prokaryotic (bacteria), though we do tend to be eukaryocentric (is that a word?) Historically, cell biology was really the coming together of 3 strands of science: Cytology, Biochemistry and Genetics. For more information see my Science Lecture slides Introduction to Cell Biology.