Microscope Basics T. Trimpe 2005 http://sciencespot.net/

Ocular lens (Eyepiece) – 10x Body Tube Nosepiece Arm Objectives Stage Stage Clips Coarse Adjustment Diaphragm Fine Adjustment Light Always carry a microscope with one hand holding the arm and one hand under the base. Base

Fill in the table on your worksheet. What’s my power? To calculate the power of magnification, multiply the power of the ocular lens by the power of the objective. Example (10x) x (8x) = 80x What are the powers of magnification for each of the objectives we have on our microscopes? Fill in the table on your worksheet. What is magnification?

Comparing Powers of Magnification We can see better details with higher the powers of magnification, but we cannot see as much of the image. Which of these images would be viewed at a higher power of magnification?

You need to know how – before you do 1 – Turn on the microscope and then rotate the nosepiece to click the lowest power (shortest) objective into place. 2 – Place a slide (letter e) on the stage and secure it using the stage clips. Use the coarse adjustment knob (large knob) to get it the image into view and then use the fine adjustment knob (small knob) to make it clearer. Once the microscope is focused on low power. You do not need to touch the high power again. Microscopes are parfocal. 3 – Once you have the image in view, rotate the nosepiece to view it under different powers. Draw what you see on your worksheet! Never use course adjustment on high power

You need to know how – before you do 4– Once you have the image in view, rotate the nosepiece to view it under different powers. The fine adjustment will give you better RESOLUTION. Resolution is the ability to distinguish between two or more objects. Draw what you see on your worksheet! Field of View is what you see under the microscope, that is why it is round. Drawings are done with pencils. 5 – When you are done, turn off the microscope and put up the slides you used. Microscopes are always stored on low power. Rules: Carry microscope with two hands. Only use special lens paper to clean microscopes Do not leave slides on microscopes. Make sure microscopes are unplugged if leaving. Power cords should always stay on the counter. The arm faces you as you use the microscope.

NEVER use coarse adjustment on high power!!!!! Let’s give it a try ... Rules: Carry microscope with two hands. Only use special lens paper to clean microscopes Do not leave slides on microscopes. Make sure microscopes are unplugged if leaving. Power cords should always stay on the counter. The arm faces you as you use the microscope. NEVER use coarse adjustment on high power!!!!!

You do not need to use the stage clips when viewing wet-mount slides! How to make a wet-mount slide … 1 – Get a clean slide and coverslip from your teacher. 2 – Place ONE drop of water in the middle of the slide. Don’t use too much or the water will run off the edge and make a mess! 3 – Place the edge of the cover slip on one side of the water drop. 4 - Slowly lower the cover slip on top of the drop. Cover Slip Lower slowly You do not need to use the stage clips when viewing wet-mount slides! 5 – Place the slide on the stage and view it first with the red-banded objective. Once you see the image, you can rotate the nosepiece to view the slide with the different objectives.

Types of Electron Microscopes Transmission electron microscopes (TEMs) pass a beam of electron through a thin specimen Scanning electron microscopes (SEMs) scan a beam of electrons over the surface of a specimen Specimens from electron microscopy must be preserved and dehydrated, so living cells cannot be viewed

Images Produced by Electron Microscopes Cyanobacteria (TEM) Lactobacillus (SEM) Campylobacter (SEM) Deinococcus (SEM) House ant Avian influenza virus Yeast Human eyelash

Light Microscope Electron Microscope Advantage Disadvantage

Using Microscopes to Visualize the Three Shapes of Bacteria Cocci (round) Bacilli (rod) Spirilla (spiral) Light microscope: Three shapes of bacteria taken with an SEM Spirilla Bacilli Cocci

COMPLETE #1-10 & OBSERVING-SKETCHING the LETTER “e”

ThThThat’s all fffolks