Question

3. Looking at some pond water under the microscope, you notice an unfamiliar rod-shaped cell about 200 mm long. Knowing that some exceptional bacteria can be asbig as this or even bigger, you wonder whether your cell is a bacterium or aeukaryote. How will you decide? If it is not a eukaryote, how will you discoverwhether it is a bacterium or an archaeon? [20]​

Answer 1

Bacteria usually have a cell wall (made of peptidoglycan or lipids) in addition to a cell membrane while eukaryotes only have a cell membrane. Eukaryotes have a nucleolus while prokaryotes do not. The two features can be easily used to differentiate the two even on a light microscope with the right staining technique.