How to Handle a Microscope - Lab Report Example

Lecturer Biology Lab Report Part A When handling the microscope it is always important to use both hands, one is placedbeneath the base and the other one is used to hold the arm. Also while walking keep it close to your body. This is important to;- a. Ensure that the microscope is secure and cannot fall and break. 2. While working with the microscope it is set at least 5 cm from the edge of the microscope. Why is this important in handling and use of the microscope? a. It ensures that the microscope is steady on the bench or table and it cannot easily fall off and break. 3. When the microscope you are using has a built in lamp. Plug it in the power source and check the position of the cord to be sure it out of the way to avoid distraction by dragging it around. 4. Begin at the top of the microscope and locate the following parts by comparing your microscope to the diagrams you have on the book or drawn. 5. Find the eyepiece at the top of the body tube which has a lens. Ensure the lens is free from dirt. If it is dirty, clean it with a lens paper gently. It is not advisable to use any other material apart from the lens paper. a. If anything else is used, the lens may be scratched and hence get damaged in the process. b. Locating the number on the eye piece helps one to know the magnifying power of that lens. The lens has a magnifying power of 10X. 6. Locate the revolving nose piece which has objective lenses. Locate the shortest objective lens. a. The number written on this objective lens is 4/0.1X. b. This is the magnifying power of this specific objective lens. 7. Locate the longer objective which is the high power objective. a. The number written on the high power objective is 40/0.65X. b. This means that the objective has a magnifying power of 40. 8. Determine if your microscope has a sharp mirror as a light source. If that is the case then turn on the light or adjust the mirror so that it will reflect the light through the condenser to the stage. 9. After you have located the stage, place a prepared slide directly over the hole in the stage. Secure the slide with the stage clips. a. This is necessary to prevent the slide from moving. 10. While observing the microscope stage from eye level, use the coarse adjustment knob until the object that you are viewing appears in the field of view. Never focus objectives downward. a. If done, the objective would break and hit the objective causing further damage. b. The high power changes your field of vision by making it more detailed and also zoomed. 11. When using a mirror to reflect light onto the specimen, avoid using direct light from the sun as it can damage ones sight. 12. Find the diaphragm. This is the aperture located directly beneath the stage. a. The diaphragm is used to regulate the amount of light that gets to the stage and illuminates the specimen under view. b. If too much light is allowed the image will be blurred and the view will not be clear. Part B: Identification of Microscope parts and their functions Eyepiece: This is the lens the viewer looks through to have a view of the specimen. It has a magnifying power of 10X or 15X. Body tube: It is the one that connects eyepiece on the upper part with the objective lens on the lower side. Arm: It is the one that connects the body tube with the base of the microscope. Coarse adjustment knob: This is the one that brings the specimen into general focus. Fine adjustment knob: It is the one that fine tunes and improves on the specimen visibility. It improves on the quality of the image being seen. Nose piece: This is a revolving turret that holds the objective lenses. The viewer rotates the nose piece to select the preferred objective lens for various tasks. Objective lenses: They form a very fundamental part of the compound microscope. They are the lenses closest to the specimen. A standard microscope has three objective lenses while some have four or five. Their power range from 4X to 100X. When focusing on the specimen be careful with the objective lens so that it does not touch the slide as this would destroy the specimen. Specimen or Slide: The specimen is the object under view. Most of the specimen viewed for biological work are mounted on slides-flat rectangular thin glasses. The specimen is placed gently on the slide and held by a cover slip which then clipped on the stage. This is important as it makes the slide to be easily inserted or removed from the microscope. It also allows the specimen to be labeled and moved without damaging it. Stage: This is the flat platform that accommodates the slide. Stage Clips: These are metal clips that serve to hold the slide into position. Stage height adjustment (stage control): These knobs move the stage left or right or up and down. Iris Diaphragm: This is an aperture that regulates the amount of light reaching the specimen. Base: It supports the microscope and it is also where the illuminator is located sometime the mirror. Part C: Making Temporary wet mount 9. State three ways in which the letter ‘e’ can be seen differently through a microscope compared to looking at it with bare eyes. a. Backwards facing away from the eye. b. The letter will be more detailed c. Its size will have increased 10. While looking at the letter, moving the slide to the right;- a. Will move the letter to the left. b. Moving the slide to the left will move the letter to the right. c. If one was tracking a microorganism and that appeared to be moving around from the right side of the vision to the left, move the slide to the left because the objects move opposite to the direction they are actually moving due to the mirror in the microscope. d. If the same organism suddenly changed direction and started to move towards the bottom of my field of vision, I would move it down because the objects move opposite to the direction they are actually moving due to the mirror in the microscope. Part D: The wide-Field Stereoscopic Microscope a. When you move the material to the left, it will move to the right in the microscopic field. b. If I move the material away from me, it moves up away from me in the microscopic field. c. The double lens in the stereoscopic microscope is responsible for producing three dimensional images. d. The production of three dimensional images is a distinct advantage as it makes it feasible to actually produce a realistic image. If your microscope has more than pair of oculars or objectives, change to the next higher magnification;- e. This increases the size of the magnified image by 3X. f. The only change that occurs is that the image formed is more zoomed and so the picture is more centered on the middle of the image. This will enable the viewer to see more details. Read More