Question

3. In a bright-field compound microscope, starting from the illuminator, follow the pathway of light: a. The first lens that provides magnification of the image is the c lor lens. b. The lens that further enlarges the image ten more times is the low power nel lens. 4. Open the iris diaphragm all the way while using the low power objective. What happens to the field of view and the quality of the image? Now close the iris diaphragm all the way. What happens to the field of view and the image? 5. Why should you always begin with scanning or low power objective? And why you should not begin with high-dry lens? 6. Complete the following table to calculate total magnification (ocular lens power X objective lens power) for the bright-field microscope: Objective Lens Objective Lens Power 4X Ocular Lens Power 10x Total Magnification 40X Scanning I Low power High-dry Oil immersion 7. Why were you asked to use only the fine adjustment knob after switching to 40X? 8. What is the highest total magnification that can be achieved using the bright-field compound microscope?_400x

Answer 1

Question 03 a.

Answer: Ocular Lens (Eyepiece Lens).

Question 03 b.

Answer: Objective Lens.

Question 04:

Answer: The function of Iris diaphragm is to adjust the amount of light which reaches to the specimen. Therefore, when iris diaphragm is opened light will illuminate the specimen and the view will be better but if it is opened all the way then the specimen will get too much light exposure and the observed image will be washed out.

Question 04 next part:

Answer: If the Iris diaphragm is closed all the way then the specimen would appear dark but increase the amount of contrast and field of view would be dark.

Question 05:

Answer: The low power makes it easier to find and locate the specimen easily and adjust the microscope to the part which is required to be observed. You should not begin with high dry lens because these lenses require more focus and if they are used directly localizing the observation part and adjustment could be difficult.

Additionally using high power objective lens needs it to be close to the specimen for better focus and using it directly could result in the lens touching the slide.

Question 06:

Answer:

Objective Lens Scanning Objective Lens Power Ocular Lens Power 10X Total Magnification 40x Low power High-dry lox 10 x 40X 10 x 100X 10 X 1DOX 400 x 1000X Oil immersion

Question 07:

Answer: Because while using high power objective lens the lens is quite close to the specimen and if you use the coarse adjustment along with the high power objective lens then the objective lens could touch the slide which would potentially cause damage to the microscope.