BIOLOGY P1

• Eukaryotic cells


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


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


  Cells where the genetic material is not enclosed in a nucleus
• What do Prokaryotic cells contain?

  • 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
• Centimeter (cm)


  One hundredth of a meter
• Millimeter (mm)


  One thousandth of a meter
• Micrometer (μm)


  One millionth of a meter
• Size of objects

  • Typical human cell is 10-20 μm in size
• Nanometer (nm)


  One billionth of a meter
• Order of magnitude


  A way to compare the approximate size of different objects
• Objects of the same order of magnitude


  • Apple and orange
• Pineapple compared to lemon

  Pineapple is one order of magnitude larger (10 times larger)
• How to determine order of magnitude


  Count the number of zeros - each zero represents one order of magnitude (10 times greater)
• Calculating order of magnitude difference


  1. Find how many times larger one object is than the other

  2. Count the number of zeros to determine the order of magnitude difference
• Eukaryotes


  Organisms whose genetic material is enclosed in a nucleus
• Nucleus


  Encloses the genetic material
• Cytoplasm


  Watery solution where chemical reactions take place
• Cell membrane


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


  Where aerobic respiration takes place
• Ribosomes


  Sites of protein synthesis
• Ribosomes are too small to be seen using a light microscope, an electron microscope is required
• Proteins carry out many functions, such as enzymes
• Eukaryotes


  Organisms whose genetic material is enclosed in a nucleus
• Nucleus


  Encloses the genetic material
• Cytoplasm


  Watery solution where chemical reactions take place
• Cell membrane


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


  Where aerobic respiration takes place
• Ribosomes


  Sites of protein synthesis
• Ribosomes are too small to be seen using a light microscope, an electron microscope is required
• Proteins carry out many functions, such as enzymes
• Specialized animal cells


  Cells that have adaptations which help them to carry out a particular function
• Differentiation


  When cells become specialized
• Sperm cells


  • Long tail to swim to ovum
  • Packed with mitochondria to provide energy for swimming
  • Contain enzymes to digest outer layer of ovum
• Fertilization


  The process where the genetic information of the ovum and sperm combine
• Nerve cells


  • Long axon to transmit electrical impulses
  • Axon covered in myelin to insulate and speed up transmission
  • Dendrites to increase surface area for connections
• Muscle cells


  • Contain protein fibers that can contract to shorten the cell
  • Packed with mitochondria to provide energy for contraction
• Muscle cells work together to form muscle tissue