How does smear preparation of cells from a liquid medium differ from preparation of cells from a solid medium? Why is it important to limit the quantity of cells used to prepare a smear? Describe the potential consequences of making a smear that is too thick. For preparation of a smear on a slide, what is the purpose of heat fixation? What problems can arise when the slide is heated in a flame? What is meant by palisade arrangement of cells? What shape does Vibrio cholerae have?