Cell Structure and Function

• Vesicle


  Small membrane bound sac that transports materials into, out of, or within the cell
• Cell membrane

  • Outer boundary of the cell that separates neighbouring cells from external environment
  • Determines which substances gets into or out of the cell
• Golgi Body


  • Flattened membranes stacked on top of each other
  • Modifies proteins and packages them for secretion from the cell
  • Vesicles are pinched off the edges of the membrane
• Mitochondria


  • Sausage shaped like structure spread throughout the cytoplasm
  • Double membrane- outer; smooth and inner one is folded towards the centre of the mitochondrion
  • Releases energy for the cell through respiration
• Nucleus


  • Usually spherical
  • Contain genetic material (mostly DNA)
  • Double membrane that has gaps, nuclear pores through which large molecules can pass
• Nucleoles


  • Made of RNA
  • DNA & Nucleoles are surrounded in jelly-like nucleoplasm
• Lysosomes


  • Small spheres that contain enzymes to break down lipids, nucleic acids, proteins and carbs
  • Breaks down materials take into or out of cell and break down organelles
• Cytoskeleton


  Consists of microfilaments and microtubules that gives the cell its shape and assists its movement of materials, organelles or the whole cell
• Ribosomes


  Small amino acids are joined together at the ribosomes to make proteins
• Endoplasmic Reticulum


  • Pair of parallel membranes that connect the cell membrane to the nuclear membrane
  • A surface where chemical reactions can occur
  • The channels between the paired membranes are used for storage or transport of materials
• Centrioles


  Small cylindrical structures located near nucleus involved in reproduction of the cell
• Cytoplasm


  • Thick fluid within cell membrane
  • Jelly-like or water material that fills all the space between nucleus and cell membrane
  • Made up of cytosol and organelles
• Cytosol


  • Controls osmotic pressure of the cell
  • 75-90% of water