After performing this activity, you should be able to:
1. handle the microscope properly;
2. identify the parts of the microscope;
3. describe what parts of the microscope can do;
4. prepare materials for microscope study;
5. focus the microscope properly;
6. compare the image of the object seen by the unaided eye and under the microscope; and
7. compute for the magnification of objects observed under the microscope.
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Procedure:
A. THE MICROSCOPE, ITS PARTS AND THEIR FUNCTIONS
1. Get the microscope from its box or the cabinet. Do this by grasping the curved arm with one hand and supporting the base with the other hand.
2. Carry it to your table or working place. Remember to always use both hands when carrying the microscope.
3. Put the microscope down gently on the laboratory table with its arm facing you. Place it about 7 centimeters away from the edge of the table.
4. Wipe with tissue paper or old t-shirt the metal parts of the microscope.
Q1. What are the functions of the base and the arm of the microscope?
5. Figure 1 shows a light microscope that most schools have. Study and use this to locate different parts of the microscope.
6. Look for the revolving nosepiece. Note that objectives are attached it. You should know that there are lenses inside the objectives.
Q2. What have you observed about the objectives?
Most schools have light microscopes with three objectives. Others have four. Usually, the shortest one marked 3x, 4x or 5x is called the scanner. The low power objective (LPO) is marked 10x or 12x while the high power objective (HPO) is marked 40x, 43x or 60x. The objectives magnify the object to be observed to a certain size as indicated by the 3x, 10x or 40x, etc. marks. If the longest objective of your microscope is marked 97x or 100x or OIO or the word “oil” on it, then it has an oil immersion objective (OIO). This objective is used to view bacteria, very small protists and fungi. The OIO