Cell Theory

Cell Theory

1. Cells

   • Smallest unit of life
   • All living things made of cells
   • Cells come from preexisting cells

2. Cell Classification

   • Prokaryotic
     • Bacteria
     • No nucleus
       • Instead, has a nucleoid region that houses DNA
     • In common with Eukaryotic
       • Exclusive to Prokaryotic
         • Pili
           • Attach cells to surfaces
         • Capsule
           • Protects cell from engulfment
         • Nucleoid region
           • Houses DNA
         • Cilia & Flagella
           • Cilia
             • Moves things along surface of cell
           • Flagella
             • Moves cell from one point to another
       • Plasma membrane
         • Protects the cell
         • Controls what enters and leaves the cell
         • Made of phospholipid bilayer
       • Cytoplasm
         • Protects cell organelles
         • Jelly like substance in between organelles
         • Site of chemical reactions
       • Ribosomes
         • Function: protein synthesis
           • Synthesis = creation
         • Small subunit + large subunit
         • Found in cytoplasm or attached to endoplasmic reticulum
       • DNA
       • Cell Wall
       • Cytoskeleton
         • Maintains shape of cell
         • Holds organelles in place
   • Eukaryotic
     • Plant and animal cells
     • Has nucleus
     • Membrane-bound organelles
       • Obtained through ENDOSYMBIOSIS
         • Endosymbiotic theory:
           • Prokaryote cells engulf other prokaryote cells -> mitochondria is engulfed first, then chloroplast
             • Prokaryotic cells that are engulfed do not get digested -> instead they live in harmony with the other prokaryotic cell (like a symbiote i.e. Venom)
     • In common with Prokaryotic
       • Plasma membrane
       • Cytoplasm
       • Ribosomes
       • DNA
       • Cell Wall
         • Only in plant cells
       • Cytoskeleton
     • Exclusive to Eukaryotic
       • Nucelus
         • Stores genetic material (keeps DNA safe)
           • Each cell has the same type of DNA, but in some cells specific instructions are turned off.
       • Endoplasmic reticulum
         • Rough endoplasmic reticulum
           • Attaches to outer membrane of nuclear envelope
           • Processes and modifies proteins
         • Smooth endoplasmic reticulum
           • Attaches to rough endoplasmic reticulum
           • Synthesizes phospholipids
       • Golgi apparatus
         • Collects, sorts, packages, and distributes materials (proteins + lipids)
       • Mitochondria
         • Site of cellular respiration (provides energy)
     • Animal Cells vs Plant Cells
       • Animal
         • Lysosomes
           • Contain digestive enzyme
             • Some scientists argue that plant cells have them too
         • Centrioles
           • Aid in cell division
         • Vacuoles
           • Lots of small vacuoles
       • Plant
         • Contain cell wall
         • Chloroplasts
           • Site of photosynthesis
         • Central vacuole
           • One big vacuole

3. Rebeca Rodríguez Petz A01723482