Experiment

Name:

OVERVIEW: 1. 2. 3. 4. 5. Field of view of the microscope. Magnification. Cells. Fresh specimens. Gram staining and Oil immersion objective lens

OBJECTIVES: By the end of this experiment, you should be able to: 1. 2. 3. 4. 5. 6. 7. determine the depth of field determine the field of view calculate the actual magnification observe cells from different tissues explain the principle and technique of Gram staining. use the oil immersion objective lens explain the principles and procedures of using a microscope

Activity 1: Field of view of the microscope A. Images under the microscope 1. Prepare a slide of the letter ‘e’ and place it onto the stage. Observe the ‘e’ slide using the 4X objective lens (low power). Focus it with the coarse adjustment knob followed by the fine adjustment knob. Draw what you have observed through the eyepiece and determine the position of ‘e’ on the stage. What happen to the final image of the specimen? 2. Move the slide slowly from left to right. In what direction does the letter move when viewed through the microscope? 3. Move the slide slowly toward you? In what direction does the letter move when viewed through the microscope? 4. In practice, enlargements beyond a certain size are meaningless. Observe the ‘e’ slide using high power. What do you observe? 5. When this happens, the limit of resolution of the LM has been exceeded. An increase in magnification without the corresponding increase in resolution is called ___________.

Biology Lab 1 1

Name: B. The depth of field

Date:

1. Observe the cross thread under 4X or 10X objective lens. 2. Note the colour of the thread. Identify the location of thread; at the top and at the bottom. 3. Remove the slide and observe the position of the thread on the slide with your eyes. Identify the location of thread; at the top and at the bottom. C. The field of view The field of view is the illuminated spot which is observed through the microscope. When we have determined the size...