Microscope Lab Report PDF

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Microscope lab report...

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Lab 1 Report Introduction to the Compound Microscope Station 1 Power of Objective Lenses 4x

Power of the Ocular 10x

Total Magnification

10x

10x

100x

40x

10x

400x

Station 2 Orientation of a Magnified Image Orientation of the Object

40x

Orientation of the Image

Path of Light through the Microscope (draw carefully – be exact)

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Explain how the internal structures within the scope refract the light to create the image that reaches the eye. The light from the source passes through the condenser, and then passes up through the slide and into the objective lens where the first magnification of the image takes place. There are some mirrors inside the body tube so that the image can travel from the objective lens, up to the body tube and to the ocular lens, so it can magnify the image a little more. This is what inverts and flips the image that reaches our eyes

Station 3 Calculating diameter of Field of View (FOV) Using the table provided, measure the diameter of the field of view under 40, 100 and 400X magnification. Power of Total Diameter of Objective Lens Magnification FOV (mm) 4 40 4.2 10

100

1.8

40

400

0.4

Explain briefly, why it is important to understand FOV. We need to understand FOV in order to calculate the precise size of the specimen.

Station 4 Calculating Size of Magnified Object Number of RBCs Number of RBCs on the diameter on the radius r¹ = 38 d¹ = 76 r² = 27 d² = 54 r³ = 35 d³ = 70 Total 200 Average 67 Calculation of size of single RBC (show calculations) 0.4 ÷ 67 ≈ 0.006 mm = 6 µm

Take a look on the net. What is the accepted size of an RBC? If your was different, why? According to LabCE (n.d), the average size of an RBC is 6-8 µm which matches our result.

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Station 5 Depth of Field (DOF) Fibre Colour Top Middle Bottom

Red Yellow Blue

Explain why it is important to understand depth of field. Since most biological specimens we will exam is several layers thick, understanding DOF will help us to examine and focus on each layer separately (Gallardo, n.d) Station 6 Depth of Field and Empty Magnification Observation 1 at 100X: What does this demonstrate? What do you see vs what you see at 400x? At 100x: We see something like a transparent mosquito with dark yellow hair around its cylindrical feet. At 400x: Everything disappears, all we see is the yellow color. It’s like “empty magnification” Observation 2 at 400X: What does this demonstrate about the absolute threshold of magnification? At 400x, the specimen is 4 times magnified compared to 100x so the image is much more “zoomed in”. However, at 400x we see nothing whereas we can see every part of the fruit fly with 100x What do you notice about the relationship between total magnification, FOV and DOF? If the total magnification increases, the FOV and DOF decrease. Which is the best for looking at specimens? 100x

Station 7 Use of the Iris Diaphragm and Manipulating Amount of Light – Examining Scypha. Use 40x and 100x and 400x. Observation 1 (40x): When we closed the light, we saw the lines clearly (more contrast) The more light we got, the more difficult it is to see the lines (less contrast) Observation 2 (100x): We see longer and bigger lines We still see it more clearly with the light being closed. Observation 3 (400x): All we saw was little dots, the image was blurry

Look up and explain the importance of stain in microscopy. As we all know, cells are usually transparent so it is important to stain them before they can be viewed with the light microscope as it helps define the specimen and make it easier to see (CliffsNotes, n.d).

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References CliffsNotes. (n.d). Staining Techniques. Retrieved from https://www.cliffsnotes.com/studyguides/biology/microbiology/microscopy/staining-techniques Gallardo, L. (n.d). Microscope/Cytology, p.8. Retrieved from http://instruct.westvalley.edu/leticiagallardo/HumanAnatomy/bio47handouts/Handouts/5Bio47_07-08Lab02_Micro.pdf LabCE. (n.d). Red Blood Cell (RBC) Size Variation. Retrieved from https://www.labce.com/spg579126_red_blood_cell_rbc_size_variation.aspx...