Lab 2 Homework assignment PDF

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This homework is for lab experiment number two...

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1.Define magnification and resolution. Compare and contrast the two. Magnification is the ratio of the image seen in the microscope versus the actual size of the object. On the other hand, resolution is the microscope’s ability to separate two points. Magnification correlates to the size on an image, while resolution relates to the clarity of the image being examined with the microscope. 2. Why does your field of view become smaller as you increase you magnification? The field of view becomes smaller as you increase the magnification because the focal plane can only focus light on a small portion of the specimen. The higher the magnification, the smaller the field of view becomes. 3. What is the focal plane? How is it limited? Where did you see this limitation occur? The focal plane influences the ability to visualize an object when using a light microscope. A focal plane becomes more limited the higher the magnification used to examine an object. This limitation is evident when one switches to a higher objective lens. The higher the magnification the smaller the focal plane because the object is now being examined at a much larger size ratio. 4. What is the primary difference between the compound microscope and the dissecting microscope? A compound microscope has the ability of magnifying an object to about 1000x, while a dissecting microscope can only magnify an object to about 100x. 5. Read up on the 100x objective (total magnification 1000x), why is it necessary to use oil immersion when using this objective? When using a very high magnification, such as 1000x, the light refraction is visible. In order to decrease the light refraction, oil immersion is used. This technique allows more light to be directed thorough the specimen being examined and therefore makes the image clearer. 6. At what point should you stop using the course adjustment knob on the compound microscope? Why should you stop using it? The course adjustment knob should spot being used while examining a specimen at high objectives. This is because the objective lens might end up colliding with the stage. This can lead to a broken objective lens or a broken slide.

7. What is the difference between the fine adjustment knob and the course adjustment knob? The fine adjustment knob is used to slightly move the stage in order to focus the object to a point where the image is clear. On the other hand, the course adjustment knob moves the stage up and down to try and make the image more focused. 8. If you were to swab you phone right now and grow the bacteria. Which microscope would be ideal to look at the bacteria? Why? A compound microscope would be the best option if I were to swab my phone and examine the bacteria. This is because a compound microscope allows for a magnification of up to 1000x. Unlike a dissecting microscope, a compound microscope allows the specimen to be examined at more than just the surface level. 9. If you were to catch a bug in the forest and wanted to identify the species. Which microscope would you use? Why? If I were to catch a bug in the forest and wanted to identify the species, I would use a dissecting microscope. This is because I would want to examine the bug while it is still alive and if I were to use an electron microscope, the specimen would have to be coated in metal ions, resulting in the death of the specimen. 10. Look up the difference between the TEM and the SEM electron microscope. Compare and contrast. Give an example of what you would look at using each microscope. A transmission electron microscope (TEM) uses the electrons that pass through the sample in order to form the image. One example for the use of a TEM could be when examining the inner structure of the mitochondria. A scanning electron microscope (SEM) produces a three dimensional image of the surface of an object. An example for a SEM could be when examining a person’s skin surface....