Microscopy Required Practical

Question 1

What is a light microscope

Answer 1

Use light and lenses to form an image of a specimen and magnify it allowing the user to see sub cellular structures

Question 2

What is an electron microscope

Answer 2

Use electrons to form an image . They have a much higher magnification than a light microscope

Question 3

Define resolution

Answer 3

The ability to distinguish 2 points on an image

Question 4

How do you prepare a slide

Answer 4

Add a drop of water to the middle of a clean slide

Cut an onion and separate it out into layers . Use tweezers to peel of some epidermal tissue

Carefully place the specimen onto the slide with the drop of water .

Add a drop of iodine solution. This is a stain . Stains are used to highlight objects in a cell

Place a cover slip onto the specimen . Stand the cover upright and tilt the slide downwards . This is done to minimize air bubbles from distorting the image

Question 5

Using the microscope

Answer 5

Clip the slide you have prepared onto the stage

Select the lowest powered objective lens

Use the coarse adjustment knob to move the stage up to just below the objective lens .

Look down on the eye piece and use the coarse wheel to move the stage into focus

Use the fine focus wheel to get a clear image

If needed you can use more powerful lenses to view the specimen