Microscopes

Question 1

What is a microscope?

Answer 1

Let us see things that we can’t see with the naked eye such as individual cells

Question 2

How do they work?

Answer 2

Microscopes use light and lenses to form an image and magnify it.
Electron microscopes use electrons instead of light to form an image and they have much higher magnification and higher resolution. We can see inside a cell with these.

Question 3

How to prepare a specimen on a slide?

Answer 3

You need to put the specimen on the slide
A slide is a strip of clear glass or plastic (quite thin)
Add a drop of water to the middle of the slide
Cut an onion into separate layers and peel off epidermal tissue with tweezers
Place the tissue on the slide
Use iodine to stain and it highlights objects in a cell by adding colour
Place cover slip on top with no air bubbles to obstruct view

Question 4

How do you observe the specimen?

Answer 4

Clip the slide on to the stage
Select lowest powered lens
Adjust with coarse adjustment knob to move up stage
Look down eye piece and focus with adjustment knob
Change to higher powered objective lens and refocus for more magnification

Question 5

What is magnification?

Answer 5

Magnification is how much bigger the image is than the real object that you’re looking at.
The calculation for this is magnification = image size ➗ real size

Question 6

How do record observations?

Answer 6

Draw with a sharp pencil
No colouring or shading
Keep sub cellular forms in proportion 
Don't forget title and labels
Write down magnification of the drawing