II. Microscope Parts, Functions, & Calculating Total Magnification - Kathy Egbert | Library

Microscope Parts and Function - Stop video at 1:30 to practice calculating magnification - the rest of the video describes the parts and functions of the microscope

Stop video at 1:30 to practice calculating magnification

You will need to be able to calculate the magnification of objects you are viewing under the microscope. To do so, you multiply the magnification of the ocular lens (eyepiece) times the magnification of the power of the objective.

Eyepiece x Objective =Total Magnification

This is important!

You need to make a note to yourself so you will have the information later during the labs.

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Did you locate the eyepiece or ocular lens on your microscope?

Your microscope has

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Did you locate the objectives on your microscope?

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Your microscope should have the 4x or scanning objective in the viewing position.

Reminder:

The 4x or scanning objective is

where you begin all work;
where you return to before you remove your slides; and
where you leave the microscope at the end of class.

No one leaves at the end of class until all microscopes are in their correct position.

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Let's practice calculating total magnification...Total magnification when the objective is in the middle position (or called low power or 10x) is:

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Total magnification when the objective is at high power (also called 40x) is:

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Total magnification of a specimen under the scanning objective is:

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Did you get the questions on calculating total magnification correct?

Parts and Functions of the Microscope starts at 1:30

You will be required to physically identify the parts of the microscope and their function on your Practicum (test) on microscopes. Be sure you have notes or whatever you need to remember the parts and their functions.

HINT: To locate a specimen

always begin at 4x and bring your slide into focus using the coarse adjustment knob; move your slide so your specimen is in the middle of your viewing area;
after in focus, then move the objective to 10x, use the fine adjustment knob to tweak it into focus, be sure the specimen is in the middle of the viewing screen;
then move to high power, 40x, and use the fine adjustment knob to tweak it into focus.

Return the objective to 4x before removing the slide! If you don't do this you may break a slide or scratch the objective lens.

Our microscopes have a mechanical stage which helps locating specimens and
following movement of live specimens

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The mechanical stage allows you to move the slide around on the stage. It consists of a slide holder and two knobs.

+ the slide holder has a lever that you move outward which opens the clip to hold the slide in place + turn one knob and the slide moves toward or away from you + turn the other knob and the slide moves left and right Locate the knobs and clips on the mechanical stage:

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Find the switch and turn on the lamp. Leave the light (lamp) on to help you locating how the diaphragm works on the next question.

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HINT: This is counter-intuitive, but less light actually makes it easier to see a specimen and its detail. If you are having difficulties seeing specimens, lower the amount of light coming in by adjusting or closing the diaphragm. Locate the diaphragm and the knob that controls it. (Be sure to turn off the lamp/light when finished.)

Very important: only use the coarse adjustment knob on the 4x (scanning)
objective. If you use the Coarse Adjustment Knob on the low or high power
objective, you may break a slide or scratch the lens. When using the low and
high power objectives, only use the Fine Adjustment Knob.

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 1 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 2 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 3 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 4 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 5 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 6 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 7 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 8 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 9 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 10 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 11 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 12 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 13 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 14 Answer:

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Use the word bank to fill in the correct terms identifying the parts of the microscope. Be sure to type answer correctly as given in the word bank. Box 15 Answer:

Next Step: Practice with a virtual microscope prior to using your microscope. Hyperlink provided below. ​Use your earbuds to listen to the instructions. Select "Get Started" as directed after the program loads.

https://www.udel.edu/biology/ketcham/microscope/scope.html

What the website looks like when you start

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Describe what the letter "e" looks like through the microscope lens.

This is a good time to look at the "e" specimen under different powers of magnification. As you increase magnification, the field of view decreases. That is why it is very important to always have your specimen centered in the middle of the field of view.

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Practice measuring specimens under "Try This" menu m1: height of letter is

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Practice measuring specimens under "Try This" menu m2 : width of cell is

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Practice measuring specimens under "Try This" menu m3: diameter of an air bubble is

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Under "Try This" - puzzles - p1 Each puzzle image is a specimen that is "off" by a bit. It may be out of focus, uncentered, too much or too little light, or several of these. Correct the view so the specimen is centered and in focus. Take a picture of the specimen once you have it in focus and insert. p1

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Under "Try This" - puzzles - p2 Each puzzle image is a specimen that is "off" by a bit. It may be out of focus, uncentered, too much or too little light, or several of these. Correct the view so the specimen is in focus and centered. Take a picture of the specimen and insert. p2

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Under "Try This" - puzzles - p3 Each puzzle image is a specimen that is "off" by a bit. It may be out of focus, uncentered, too much or too little light, or several of these. Correct the view so the specimen is centered and in focus. Take a picture of the specimen and insert. p3

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Under "Try This" - puzzles - p4 Each puzzle image is a specimen that is "off" by a bit. It may be out of focus, uncentered, too much or too little light, or several of these. Correct the view so the specimen is centered and in focus. Take a picture of the specimen and insert. p4

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Under "Try This" - puzzles - p5 Each puzzle image is a specimen that is "off" by a bit. It may be out of focus, uncentered, too much or too little light, or several of these. Correct the view so the specimen is centered and in focus. Take a picture of the specimen and insert. p5

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Under "Try This" - puzzles - p6 Each puzzle image is a specimen that is "off" by a bit. It may be out of focus, uncentered, too much or too little light, or several of these. Correct the view so the specimen is centered and in focus. Take a picture of the specimen and insert. p6

Check with Mrs Egbert about your score. If you were successful, then you are
ready to start Part III on Microscopes.