cell structure(biology)

• Eyepiece lens


  The lens closest to your eye, normally makes the image ten times bigger than real life
• Objective lens


  • There are three lenses of different strength which can be used to look at the slide in more detail
• Stage


  The place where you put a microscope slide
• Diaphragm


  Controls the amount of light that goes onto the microscope slide
• Light


  Projects light onto the microscope slide
• Base


  Keeps the microscope steadly on the desk and stops it from tipping over
• Arm


  Holds the eyepiece lens above the stage
• Fine focus knob


  Used to get the microscope slide into focus so the image is very sharp
• Coarse focus knob


  Used to get the microscope slide into focus so that you can see the image clearly
• Mitochondria


  Site of respiration (energy release from glucose)
• Cell membrane


  Controls movement of substances in and out of the cell
• Nucleus


  Contains genetic info needed to make new cells
• Cytoplasm


  Jelly-like substance, made up mainly of water, where cell reactions take place
• Ribosome


  Where protein synthesis occurs, proteins are made
• Light microscopes use a beam of light to see an object
• Light microscopes magnify up to 2000x
• Light microscopes are relatively cheap
• Light microscopes can be used anywhere, don't need specialised training to use
• Light microscopes can observe living specimens
• Light microscopes have a resolution of approximately 200mm
• Magnification


  How much larger an image is compared to the original
• Resolution


  Ability to distinguish between 2 points
• Electron microscopes use a beam of electrons to form an image
• Electron microscopes magnify up to 2000000x
• Transmission electron microscopes produce 2D images with very high magnification and resolution
• Scanning electron microscopes produce 3D images with lower magnification
• Electron microscopes have a resolution of 0.2mm
• Electron microscopes are very large and very expensive
• Electron microscopes have to be kept in carefully controlled rooms and need skilled users
• 1km


  1000m (meters)
• 1m


  100cm (centimeters)
• 1cm


  10mm (millimeters)
• 1mm


  1000 μm (micrometers)
• 1 μm


  1000 nm (nanometers)
• 1mm


  1 x 10^-3
• Cell wall


  Made of glucose, provides strength and support
• Vacuole


  Contains cell sap (sugars, salts and water)
• Mitochondria


  Contains chlorophyll - site of photosynthesis, traps sunlight
• Chloroplast


  Site of photosynthesis, traps sunlight
• Ribosome


  Where protein synthesis occurs