Elaborate the working scheme of scanning electron microscope.

Using electron microscopes to research cells

The below photograph was taken using an electron microscope and shows a small part of a plant cell.

Electron microscopes are used to produce magnified images of cell components. The magnification of an image is how much larger it is than the actual structures. Work out the magnification of this photo by following these steps:

a) Use a ruler to measure the diameter of the nucleus in the photo. Do this in millimeters, not centimeters. 

b) Convert the diameter in millimeters to micrometers.

c) Divide the diameter of the nucleus in the photo by its actual diameter, $3.3 \mathrm{\mu m}$. Be sure that both diameters are in micrometers. The value that you have calculated is the magnification of the photo.

Compare the two diagrams given below. Name the structures in an animal cell that can be seen with the electron microscope but not with the light microscope.

Compare the two diagrams given below. Name the structures in a plant cell that can be seen with the electron microscope but not with the light microscope.

1. Describe how can a microscope be used to observe some blood cells. 

LSs and TSs of striated muscle fibres were examined in an electron microscope. In the given picture shows drawings of the structures visible in a sarcomere in LS and TS as seen in a TEM. Explain why an electron microscope rather than a light microscope was used to study these sections.

Copy and complete the table which compares light microscope with an electron microscope.