2. Microscopes

What is the formula for calculating the magnification of a microscope?

• M=I/A

• M=A/I

• M=IxA

• Magnification = eyepiece lens

  x

  objective lens

What is the formula for calculating the magnification of a drawing or photograph?

• M=IxA

• M=I/A

• M=A/I

• M=I+A

What do you use to view cells more clearly under the microscope?

• A dye

• A stain

• Colouring

• Ink

What is the advantage of using a light microscope over an electron microscope?

• Greater magnification

• Greater resolution

• Can view living cells

• Easier to use

What is a mounted needle used for when preparing a slide?

• To obtain the cheek cell sample

• To stir the stain into the sample

• To gently lower the cover slip onto the slide

• To hold the slide in place

What is the advantage of using an electron microscope?

• Able to view living tissue

• Greater magnification and resolution

• Cheaper to buy

• Able to magnify up to 1000 x greater

A photograph of an onion cell measures 10mm (image size)

The actual size of the cell is 0.5mm

What is the magnification of the image?

• x 0.2

• x 2

• x 20

• x 200

A microscope has a total magnification of x200

If the eyepiece lens has the power of x5, what is the power of the objective lens?

• x40

• x205

• x195

• x1000

Is this an image obtained from a light or an electron microscope?

• Electron

• Light

identify the structure labelled A in this image of a cheek cell

• Cell membrane

• Chloroplast

• Mitochondrion

• Nucleus