microscopy

• What are disadvantages of light microscopes compared to electron microscopes?

  Relies on light

  Longer wavelength

  Lower resolution

  Lower maximum magnification
• Definition of magnification

  How much bigger an image appears compared to the real object
• What are the 2 types of microscopes?

  Light microscope and electron microscope.
• 5 advantages of light microscopes compared to electron microscopes

  Cheap

  Easy to use

  Small and easy to transport

  Produce colour images

  Can see living specimens (eg live cells)
• what is the conversion rate from micrometers to metres?

  1 μm or 1micrometer is equal to 10^-6 m
• why do electron microscopes have a greater magnification and resolution than light microscope?

  They use a beam of electrons rather than light waves and electrons have a shorter wavelength than light waves
• define resolution

  how much detail you can see in the image
• what is the magnifying power of a light microscope

  magnification: x 2000
• what is the magnifying power of an electron microscope

  magnification: x 2,000,000
• how many nm are there in 1 μm?

  1000
• what is the equation for magnification?

  magnification = image size divided by object size
• 5 disadvantages of electron microscopes compared to light microscopes

  Expensive

  Difficult to use

  Large and difficult to transport

  Images only in black and white

  Can only view dead specimens
• What is the role of a microscope

  Designed to magnify small objects so they appear larger
• What are the main advantages of electron microscopes compared to light microscopes

  Electron microscopes have a greater resolution and magnification.

  Can be used to see details within sub cellular structure.
• How does a light microscope work?

  Light passes through the specimen, objective lens, the eyepiece lens and into your eye.

  The 2 lenses magnify the image and cause the image to be much larger than the real object