Chapter 9: The Microscopic World

  • Most living this contain many cells.  The human body contains TRILLIONS of cells.  Did you know that some living organisms are made up of only ONE cell?  Some of these single- celled creatures have been found living in many places from volcano openings, to the human stomach! In this chapter you will learn how organisms made up of only one cell carry out necessary life functions.  You'll also learn about invaders of cells called VIRUSES.  It's a strange world when you start looking under a microscope!
    Key Questions:
    1) What is a protozoan and how does it survive with only one cell?
    2) Are all bacteria harmful?
    3) Is a virus alive or not?