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Microscope

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Biology 100 – K. Marr (Revised Spring 2010)

Lab 2. Microscopic Observation of Cells
Prelab Assignment 1. Before coming to lab, read carefully the introduction and procedures of each part of the experiment. If you and your group members are not familiar with the procedure before coming to lab, you may have difficulty completing this exercise during the lab period. 2. Answer the Prelab Questions on the first three pages of the report sheet and be prepared to hand them in at the start of your lab class. Please be aware that you need to go online to answer prelab question #3. Goals of this Lab Exercise After completing this lab exercise you should be able to..... 1. Identify the parts of a compound light microscope and use a microscope to competently examine biological samples 2. Determine the diameter of the field of view for the various objectives of a microscope 3. Accurately sketch, describe and cite the major functions of the structures and organelles of the cells examined in this lab exercise 4. Estimate the size of specimens viewed with a microscope. The Microscope The microscope is one of the principal tools of the biologist. Without the microscope, many of the great discoveries of biology would never have been made. The light compound microscope, illustrated in Figure 1, is the type of microscope most commonly used. Proper, comfortable use of the instrument demands practice. The practice afforded you in this exercise depends upon familiarity with the parts of the microscope and with their interactions.

Figure 1. A typical compound light microscope used in many biology labs.

1

Lab 2 Biology 100 Note each of the following features of the microscope and there individual uses to allow you to take full advantage of the use of a microscope.  Ocular or Eyepiece—contains a lens that magnifies the specimen (usually 10x)  Revolving Nosepiece—used to change

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