Cell Biology

• Modern Cell Theory

  1. cells are the smallest living unit of all organisms
  2. all living things are made of cells
  3. cells come from pre-existing cells
• DNA


  a cell's genetic material
• Ribosomes


  makes protein
• Cytoplasm


  semi-fluid that contains all organelles
• Cell membrane


  also called "plasma membrane" which controls what goes in and out of a cell
• Eukaryotes


  unicellular and multicellular organisms from domain Eukarya
• Prokaryotes


  unicellular organism from domains Archaea and Bacteria
• Cell wall is something most prokaryotic and some eukaryotic cells have
• Prokaryotic cells' organelles are not membrane-bound

  • no nucleus to contain DNA (meaning DNA of prokaryotic cells are free-floating)
• Unicellular


  organisms that are made of one cell
• Multicellular


  organisms that are made of many cells
• Cytoskeleton


  a collection of fibers providing support for the cell and its organelles
• Nucleus


  control center of a cell

  contains DNA and nucleolus in eukaryotic cells
• Nucleolus

  produces ribosomes