1.1.d Explain and distinguish between resolution and magnification, with reference to light microscopy and electron microscopy
1.1.e Calculate actual sizes of specimens from drawings, photomicrographs and electron micrographs
RESOLUTION VS MAGNIFICATION:
Resolution: The ability to distinguish between two separate objects that are very close together. The higher the resolution, the greater the detail of the image.
Magnification: The number of times larger an image is compared with the real size of the object.
LIGHT VS ELECTRON MICROSCOPES:
- There are two different types of microscopes: light and electron.
- Transmission electron and scanning electron microscopes are two examples of electron microscopes.
🤯 As you can see from the table above, using an electron microscope will produce a more detailed photo of the microscopic object because it has a nearly 400x better resolution than using a light microscope!
CALCULATING ACTUAL SIZE OF MICROSCOPIC OBJECTS:
As explained in another article, to calculate the magnification, we use the following triangle:
Therefore, to calculate actual size, we simply rearrange the formula to:
Actual size (A) = Image Size with Ruler (I) ÷ Magnification (M)
⚠️⚠️The above triangle is extremely useful! Remembering it will come in handy for other calculations (such as calculating magnification) should a question on the above appear in a GCE CIE Biology exam!
That's it! Till next time! 🙌
- Aryal, S., & Beridon, I. (2018, September 26). Differences between Light Microscope and Electron Microscope. Retrieved from https://microbiologyinfo.com/differences-between-light-microscope-and-electron-microscope/
- Jones, M., & Parkin, M. (2018). Cambridge International As and A level biology. Cambridge: Cambridge University Press.
- Linear Magnification. (2013, March 25). Retrieved from http://jessbiologyrevision.blogspot.com/2013/03/linear-magnification.html