bio paper 1

• Plant cells have a cell wall, permanent vacuole and chloroplasts
• Eukaryotic cells


  Cells that contain their genetic material enclosed in a nucleus
• Eukaryotic cells


  • Contain a nucleus
  • Contain a cell membrane
  • Contain cytoplasm
• Prokaryotic cells


  Cells where the genetic material is not enclosed in a nucleus
• Prokaryotic cells


  • Do not have a nucleus
  • Have a cell membrane
  • Have a cell wall
  • Contain cytoplasm
  • May have plasmids
• Prokaryotic cells


  Are much smaller than eukaryotic cells
• Eukaryotic cells


  Cells that contain their genetic material enclosed in a nucleus
• Eukaryotic cells


  • Contain a nucleus
  • Contain a cell membrane
  • Contain cytoplasm
• Prokaryotic cells


  Cells where the genetic material is not enclosed in a nucleus
• Prokaryotic cells


  • Do not have a nucleus
  • Have a cell membrane
  • Have a cell wall
  • Contain cytoplasm
  • May have plasmids
• Prokaryotic cells


  Are much smaller than eukaryotic cells
• Eukaryotic cells include animal and plant cells
• Prokaryotic cells include bacterial cells
• Animals are eukaryotes, their genetic material (DNA) is enclosed in a nucleus
• Nucleus


  Encloses the genetic material
• Cytoplasm


  Watery solution where chemical reactions take place, including the first stage of respiration
• Cell membrane


  Controls the molecules that can enter and leave the cell
• Mitochondria


  • Where aerobic respiration takes place
• Ribosomes


  • Sites of protein synthesis, proteins carry out many functions like enzymes
• Mitochondria and ribosomes are too small to be seen using a light microscope, an electron microscope is required
• Plant cell


  Differs from animal cells in regular shape, packed with green structures (chloroplasts)
• Plant cell


  • Contains nucleus, cytoplasm, cell membrane, mitochondria, ribosomes
  • Contains chloroplasts, cell wall, permanent vacuole
• Nucleus


  Contains genetic material
• Cytoplasm


  Where chemical reactions take place
• Cell membrane


  Controls which molecules enter and leave the cell
• Mitochondria


  Carry out aerobic respiration
• Ribosomes


  Site of protein synthesis
• Chloroplasts


  Contain chlorophyll and are sites of photosynthesis
• Cell wall


  Made from cellulose, strengthens the cell
• Vacuole


  Large permanent structure filled with cell sap, helps give the cell its shape
• Plant cells are eukaryotes
• Algae are very simple forms of plant life and also have a cellulose cell wall
• Microscopes


  • Allow you to see the outlines of cells
  • Allow you to see finer details due to greater resolving power and higher resolution
• Electron microscopes


  Provide higher magnification and resolution compared to light microscopes
• Light microscopes


  Provide lower magnification and resolution compared to electron microscopes
• Cells are usually a few micrometers (μm) long
• Converting μm to mm

  Divide by 1000
• Preparing a slide for microscopy

  1. Add a drop of water in middle of a slide

  2. Cut onion and separate into layers, use tweezers to peel off epidermal tissue

  3. Put epidermal tissue into water on the slide

  4. Add a drop of iodine (stain)

  5. Place a cover slip
• Using a light microscope

  1. Clip slide onto the stage

  2. Look into eyepiece and use the coarse adjustment knob to move stage down until it's focused

  3. Adjust the focus with the fine adjustment knob
• Cell differentiation


  Process by which a cell changes to become specialised for its job