Cells and Organelles

Cells and Organelles

1. Plasma Membrane

   • trilaminar unit
     • TEM
       • hydrophobic doesnt show up
     • glycocalyx
       • oligosaccharides
         • cell-cell recognition
   • composition
     • phospholipids
     • cholesterol
     • proteins
     • oligosaccharides
       • covalent linkage
         • phospholipids
   • function
     • selective barrier
       • regulates passage
         • maintain ion gradients
       • facilitates passage
     • cell communication
   • Fluid Mosaic Model
     • phospholipid bilayer
       • proteins inserted
         • move w/in fluid lipid phase
           • experiment
             • hybrid cells
               • fluorescent markers
                 • diffuse throughout
         • integral
           • firmly embedded
         • transmembrane
           • span entire membrane
             • hydrophobic aa
           • one pass
             • single hydrophobic region
           • multipass
             • several hydrophobic regions

2. Cytosol

   • function
     • support
       • organelles
     • medium
       • diffusion
   • composition
     • viscous fluid
     • dissolved solutes
       • ions
       • amino acids
       • lipids
       • carbs

3. Ribosomes

   • function
     • synthesize proteins
       • binds mRNA
       • positions tRNA
       • free
         • cytosolic
         • cytoskeletal
         • imported
           • nucleus
           • mitochondria
           • peroxisome
       • ER associated
         • incorporated
           • membranes
         • stored
           • lysosomes
         • secreted
   • composition
     • protein
     • rRNA
     • subunits
       • large and small
   • Nissl bodies
   • location
     • free
       • cytoplasm
     • ER associated
       • RER

4. Protesomes

   • location
     • cytoplasm
   • function
     • degrade proteins
       • denatured
       • nonfunctional
       • unnecessary
       • individual molecules
         • not whole organelles
     • restrict actions
       • temporal

5. Endoplasmic Reticulum

   • Rough ER
     • functions
       • protein synthesis
         • transported
           • plasma membrane
           • secretion
           • lysosomes
       • glycosylation
         • glycoproteins
         • post-trans mod
       • protein asembly
         • multi-chain
   • Smooth ER
     • lacks ribosomes
     • distinct functions
       • glycogen metabolism
       • lipid metabolism
       • detox rxns
       • Ca2+ sequestration