bacteria

• Endoplasmic Reticulum (ER)


  Within the antiphain
• Rough ER


  • Synthesis of hormones & parti
• Smooth ER


  • Synthesis of lipids
• Golgi apparatus


  Post office of cell: modifies proteins before releasing into the cell, produces polysaccharides
• Lysosome


  Digestive compartment, hydrolytic to digest macromolecules into smaller particles
• Phagocytes


  • Digestion of external molecules
• Autophagy


  • Old cell parts are used and recycled into new ones
• Vacuoles


  Membrane bound, empty of cytoplasm, filled with fluid, key in storage
• Mitochondria


  • Convert chemicals into energy in the cell, cellular respiration occurs here
• Chloroplasts (only in plant cells)


  • Convert light energy into chemical energy
• Cytoskeleton


  Mechanical support, moves things around the cell
• Animal cell similarities


  • Nucleus
  • Cytosol
  • Cell membrane
  • Mitochondria
• Plant cell differences


  • Cell wall
  • Chloroplasts
• Cell membrane


  Separates the cell from the outside, controls materials flowing in and out, selectively permeable
• Fluid mosaic model


  Phospholipids move within the membrane
• Phospholipids


  • Building blocks of the cell membrane, made of glycerol, two fatty acid tails, and a phosphate group
• Amphipathic


  Both hydrophilic and hydrophobic
• Unsaturated lipids


  Have a kinked structure, prevent close packing
• Saturated lipids


  Pack closely together
• Cholesterol


  • Reduces membrane fluidity, restrains movement, prevents solidification at low temperatures, increases fluidity at moderate temperatures
• Integral membrane proteins


  Integrated into the membrane, have hydrophobic regions that span the membrane
• Peripheral membrane proteins


  Loosely bound to the surface, found inside and outside the membrane
• Transport proteins


  • Allow hydrophilic molecules to cross the membrane
• Selective channels


  • Allow specific ions and molecules to cross the membrane
• Cell-cell recognition


  • Some glycoproteins act as receptors
• Enzymatic activity


  • Enzyme active sites
• Intercellular junctions


  • Long lasting connections between cells
• Signal transduction


  • Receptors
• Attachment to cytoskeleton


  • Stabilizes cell shape
• Membrane carbohydrates


  Form glycoproteins and glycolipids on the outside surface, allow cell recognition and immune system function
• Membrane sidedness


  Integral to function, distinct inside and outside layers
• Membrane permeability


  Nonpolar molecules cross easily, larger polar molecules don't, charged molecules don't cross easily
• Transport mechanisms


  • Channel proteins, carrier proteins, diffusion
• Osmosis


  Movement of solvent across a semipermeable membrane towards higher solute concentration
• Water balance


  Living cells can only tolerate certain amounts of osmotic pressure, isotonic, hypertonic, hypotonic
• Active transport


  • Requires energy to move molecules against concentration gradient, usually uses ATP
• Bulk transport


  • Moves large volumes of molecules via exocytosis and endocytosis
• Plants have cell walls