Comparing Light Microscopes and Electron Microscopes

This lecture covers electron microscopes, explaining their high cost and limited availability in schools. It details how they use electron beams instead of light to achieve magnification up to two million times, offering high resolution due to short electron wavelengths. The lecture also discusses the need for specimen preparation, often resulting in dead samples. Two types of electron microscopes are introduced: scanning, which provides 3D images, and transmission, which offers 2D images. A comparison with light microscopes highlights the differences in magnification and resolution.

Why are electron microscopes not commonly found in high schools?

• They are not effective for educational purposes.

• They are extremely expensive.

• They are too large.

• They are too complex to use.

What does an electron microscope use to produce an image?

• Magnetic fields

• Electron beams

• Light beams

• Sound waves

Up to how many times can an electron microscope magnify an object?

• 400 times

• 1500 times

• 2 million times

• 1 billion times

What is a disadvantage of using electron microscopes?

• They are not accurate.

• They have low resolution.

• Most specimens need to be dead.

• They can only be used in the dark.

What contributes to the high resolution of electron microscopes?

• High intensity of light

• Advanced software

• Long wavelengths of electrons

• Short wavelengths of electrons

What is the main difference between a Scanning Electron Microscope (SEM) and a Transmission Electron Microscope (TEM)?

• SEM is used for live specimens, TEM for dead specimens.

• SEM is cheaper than TEM.

• SEM produces 3D images, TEM produces 2D images.

• SEM uses light, TEM uses electrons.

What does a Scanning Electron Microscope (SEM) do?

• It magnifies objects up to 400 times.

• It uses sound waves to create an image.

• It bounces electrons off the surface of an object.

• It uses light to produce an image.

What does a Transmission Electron Microscope (TEM) allow you to see?

• The movement of live specimens

• The external surface of an object

• The internal structure of a thin section

• The color of an object

Tags

NGSS.HS-PS1-3

Which type of microscope produces a 3D image?

• Compound microscope

• Scanning Electron Microscope (SEM)

• Transmission Electron Microscope (TEM)

• Light microscope

Which type of microscope is commonly used in high school biology classes?

• Atomic Force Microscope (AFM)

• Light microscope

• Transmission Electron Microscope (TEM)

• Scanning Electron Microscope (SEM)