B1 : Microscopes and Magnification Flashcards
Name all the parts of a microscope
Objective lens, Eyepiece, Stage, Stage Clips, Fine Focus, Course Focus, Arm
How do you calculate magnification
M = I / A M = Magnification I = Image size A = Actual size
Which microscope is more expensive?
Electron
What is the magnification on an electron microscope?
X2000000
What is the magnification on a light microscope?
X1000-2000
What part of the microscope would you use to make an image bigger?
Change the objective lens to a higher magnification
What part of the microscope would you use to make an image clearer?
Course or fine focus to improve the clarity.
How do you improve the focus of a microscope?
Using the fine focusing knob
How do you increase the magnification of an image?
Change the objective lens to a higher magnification.
Boris is looking at a fuzzy image of a cell “I need to increase the magnification by changing the objective lens.” Is he correct? Give a reason for your answer
He is incorrect if the image is fuzzy then he needs to use the course and fine focus knobs to improve the clarity of the image. Altering the magnification would increase or decrease the size of the image.
Outline the method that a student would need to follow in order to prepare an onion slide. Include the following terms: Iodine, Onion, Upper Layer, tweezers, Glass slide, Cover Slip, Pipe.
Take a slide.
Place the specium (upper layer of the onion skin) on to the centre of the slide using tweezers to fo this. Ensure that it as flat as possible on the slide.
Add a drop of iodine to your sepcium using the pipette.
Take a cover slip and put one side of it on the slide over the onion skin.
Using a mounting needle slowly lower the cover slip in place.
The slide is now ready to be viewed under the microscope.
