A student is reviewing different microscopy techniques to determine the best method for imaging various cellular components. Which of the following statements, A to D, regarding microscopes is correct?
A light microscope with a ×12.5\times 12.5×12.5 eyepiece lens and a ×40\times 40×40 objective lens has an overall magnification of ×52.5\times 52.5×52.5 because lens magnifications are additive.
Scanning electron microscopes (SEMs) use electromagnetic lenses to focus a beam of electrons onto the surface of a specimen, producing high-resolution, three-dimensional images of its external features.
Laser scanning confocal microscopes are only suitable for imaging thin, dead specimens because the high-intensity laser beam cannot penetrate thick tissues and instantly destroys living cells.
The resolution of a transmission electron microscope is limited to approximately 200 nm200\text{ nm}200 nm because the wavelength of an electron beam is longer than that of visible light.
22 exam-style questions on OCR A A Level Biology Cell structure. Each one has a worked solution and a mark scheme showing where the marks go.