Study Guide Quiz 1 These are the important topics to prepare for the quiz # 1. 1. Compound Microscope: major parts, especially names and functions. 2. 4-Basic Rules of microscopy: a) support with both hands and cord coiled around arm b) Use only lens paper. Use sweeping motion to clean. Do not use circular or to-and-fro motion c) Microscope must be in lowest power (scanning objective lens for your microscope) when start using or storing a microscope, and removing or placing a slide from/on a microscope d) Never use coarse adjustment when on high power. 3. Ocular lens = Eye-piece – 10X…..X indicates magnification. 4. Objective lenses – Low Power = 10X , High Power = 40X and Oil Immersion = 97X 5. Magnification = size of the image / size of the object 6. Low power magnification (10X * 10X) = 100; High Power Magnification (10X * 40X) = 400 and Oil Immersion magnification (10X * 97X) = 970 7. Focusing: images are inverted = both upside down and reverse (left-right). When the object or stage moves to right image moves to left and when object or stage moves up the image moves down and vice versa. Scanning and Low Power focusing is done with coarse adjustment and High power focusing is done with Fine adjustment. 8. Microscope Field: Determining the size of objects. The total area seen through the ocular lens. It is largest under scanning objective lens (4X), large under low power objective (10X) and small under high power objective lens (40X). It is measured as Low Power Diameter (about 1.8mm) and High Power Diameter (about 0.45mm) for your microscope. 9. Depth of Field: It is the horizontal thickness below the objective lens of your microscope where the object is in Sharp Focus. The following table compares the depth of field of 2 objectives.

Low power Objective High Power Objective

a) Greater in height a) Lesser in height

b) Far from end of objective b) Near from end of objective 10. Parfocal: Compound microscope is in focus at low power magnification and you rotate the nosepiece to high power, microscope should still be almost in focus. 11. Scientific Method: main steps are Observation  Question  Hypothesis  predictions  Testing Conclusion and Analysis (hypothesis supported or rejected)  many different workers repeat testing with new predictions using many different ways  If supported  Principle / Law  related laws when fully established  Theory in Science (cell theory, evolution theory, gene theory etc.). 12. Scientific Method begins with Observation. 13. Hypothesis = possible explanation = testable statement. 14. Theory is more comprehensive than hypothesis. Theory has been tested by many workers from different ways. 15. Study parts of Microscope from the diagram and remember their functions from your notes/ lab manual. 16. Study scientific method from your text book or notes.