Observe: An organelle is a cell structure that performs a specific function. Observe the samples below under the highest magnification. Click the Show labels checkbox to label the organelles. List the organelles and approximate size of the cells in each sample. Sample Organelles Estimated size (μm) Mouse skin Fly muscle Maple leaf Elodea Fungus What do all of these samples have in common? In eukaryotic cells, genetic material is contained inside a distinct, membrane-bound nucleus. Plant and animal cells are classified as eukaryotes. Observe: Click on the cow and observe E. coli under the highest magnification. Notice the microscope magnification is larger for this organism, and notice the scale bar is smaller. What is the approximate size of E. coli? What organelles are present in E. coli? What organelle is missing from E. coli? E. coli is an example of a bacteria. Bacteria are classified as prokaryotic cells because their DNA is not contained in a membrane-bound nucleus. Compare: Look at the Sand/silt sample under the microscope. Turn on Show labels. Does sand/silt have any internal structures? Do you think sand or silt is alive? Explain.