Define the term, Resolution

Define the term, Magnification

What is the formula to work out magnification?

Optical microscopes form an image using what?

The maximum useful magnification of a light microscope is x_____

The maximum resolution of a light microscope is what? Give some organelles you CAN'T see using an optical microscope.

To view a specimen under an optical microscope, what much you prepare?

What is the first step in preparing a temporary mount?

After the specimen is on the slide, what happens next when preparing a temporary mount?

What is the final step of preparing a temporary mount?

What does TEM stand for?

A TEM uses what in order to produce an image?

What type of image does a TEM produce?

The electron beam has a very short wavelength, what does this mean for a TEM?

The specimen used in a TEM has to be very thin, why?

TEM have a high resolution, what does this mean in terms of organelles?

The image produced on a TEM is black and white or, grey-scale. Why is the image produced a grey-scale image?

What does SEM stand for?

Is the resolution of a SEM higher, or lower, than that of a TEM. Can you give the resolutions of both?

Describe a feature about the image a SEM produces

Describe vaguely how an image from a SEM is produced

Electrons from a TEM pass through the specimen, where as electrons from a SEM only scan it. What does this mean about the thickness of a specimen from each microscope?

The system of both TEM's and SEM's are in a vacumn, what limitation does this make?

In order to show up different parts of the specimen, is has to undergo a complex staining process, what limitation does this make?

Preparation of specimens for electron microscopes is a complex process with many limitation and difficulties, what does this mean?

There are 3 main steps of cell fractionation and ultracentrifugation, name them and give a sentance to what occurs in them.

Describe and explain the HOMOGENISATION step in cell fractionation.

The homogenate solution should ISOTONIC, what does this mean and why is this a required condition for the homogenate?

Another condition the homogenate should be is ICE-COLD. Explain why the solution needs to be so cold.

The homogenate also has to be the correct pH, what can be added to ensure a steady pH and explain why it is needed.

The second step of cell fractionation and ultracentrifugation is filtration and getting rid of the 'big bits'. Describe how this works.

The final step of this process, is ultracentrifugation. Fill in the blanks:

The tube of _______ is placed in the ________ and spun at a _____ speed. The heaviest __________ fall to the _______ of the test tube and form a thick _________.

After being spun at a low speed, there is a fluid at the top of the test tube. What is this called?

After the supernatant is removed, what happens to it?