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A-level Biology Question (AQA)

Can someone help me with this question:

https://docs.google.com/drawings/d/1zmmVf5bMhivQJTLeB8BXbz-kbNca0KfHLk0qmFd88t4/edit?usp=sharing

The mark scheme says its a scanning electron microscope, im confused how they know the difference (if its a transmission electron microscope or scanning electron microscope).
The evidence is apparently because it is a 3D image, I don't get that either, doesn't transmission electron microscopes also have a 3D image and only optical ones have 2D images??
Original post by jivinion
Can someone help me with this question:
https://docs.google.com/drawings/d/1zmmVf5bMhivQJTLeB8BXbz-kbNca0KfHLk0qmFd88t4/edit?usp=sharing
The mark scheme says its a scanning electron microscope, im confused how they know the difference (if its a transmission electron microscope or scanning electron microscope).
The evidence is apparently because it is a 3D image, I don't get that either, doesn't transmission electron microscopes also have a 3D image and only optical ones have 2D images??

No, TEM is only 2D image (electron pass through sample). SEM is 3D image (as reflected electrons from surface are detected).
laser scanning confocal microscope is 2D image (one plane) or 3D image (multiple plane).
Light microscope is 2D image (photon pass through sample).

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