Biology 172 Lecture 9

  1. Lysosomal storage diseases
    40 inherited diseases caused by defects in lysosome function
  2. Peroxisomes
    • with processes that metabolize hydrogen peroxide (H2O2)
    • also involved in fatty acid metabolism (oxidation)
  3. Properties of Eukaryotes: Synthesis
    • ribosomes
    • Rough ER
    • Smooth ER
  4. Where are proteins made?
    on Ribosomes
  5. Ribosomes free in cytoplasm
    Proteins destined for organelles, cytosol
  6. Ribosomes bound to ER (rER)
    • Proteins of the endomembrane system
    • Proteins to be exported / secreted
  7. Ribosomes in energy-processing organelles
    Some proteins in mitochondria, chloroplasts
  8. Endoplasmic Reticulum
    organelle made of complex out-foldings of the outer nuclear membrane
  9. Rough ER
    • has ribosomes attached
    • modifies proteins and directs their transport
  10. Smooth ER
    • lacks attached ribosomes
    • involved in lipid and carbohydrate synthesis, steroid hormone production, detoxification
  11. Export - thru the Endomembrane System
    • Synthesis on rER or in ER
    • Transport to Golgi
    • Glycosylation
    • Exocytosis / Secretion
  12. Vesicular transport
    transport vesicle forms at donor compartment, goes to donor compartment to deliver membrane and content
  13. Movement
    • ER
    • Golgi
    • Plasma membrane
  14. Golgi Apparatus
    • organelle containing stacks of membranes
    • functions in modification and targeting of proteins
    • generates vesicles that go to many destinations
  15. The Endomembrane System, The Secretory Pathway
    An integrated network of molecular trafficking
  16. Organelles of the Secretory Pathway
    • ER
    • Golgi
    • plasma membrane
    • lysosome
    • endosome
  17. Animal pancreatic cell
    Exports digestive enzymes
  18. Exocytosis
    vesicle membrane is added to the plasma membrane and contents are released from the cell (secretion)
  19. Endocytosis
    internalization of plasma membrane and extracellular contents are internalized
  20. Receptor - mediated Endocytosis
    • Recycling of receptors (proteins) from lysosome back to plasma membrane; e.g. during uptake of cholesterol from blood stream
    • Some receptors are degraded in the lysosome
  21. Ribosomes bound to rER
    • Proteins of the endomembrane system
    • Proteins to be exported / secreted
  22. Co translation transport
    protein is synthesized and transported into ER at the same time
  23. Ribosomes free in cytoplasm
    Proteins destined for organelles, cytosol
  24. Post-translational transport
    protein is completely synthesized and released from the ribosome before transport
  25. Proteins have targeting signals
    a molecular address tag
  26. Secretory pathway proteins are targeted to the ER by ...
    a signal sequence
  27. Protein sorting and vesicle transport
    • 1. Proteins are tagged
    • 2. Proteins are sorted
    • 3. Vesicles bud
    • 4. Proteins interact with receptors
    • 5. Delivery
  28. Sorting within the secretory pathways occurs via ...
    sorting signals
  29. Energy-processing chemical reactions
    • cellular respiration in mitochondria
    • photosynthesis in chloroplasts
  30. Two membrane systems
    • Outer membrane acts as boundary
    • Inner membrane with energy reactions
  31. Semi-autonomous organelles
    • With some of their own DNA and Ribosomes
    • Codes for some of their own proteins
  32. Chloroplast (plants and algae)
    • organelle that carries out photosynthesis
    • composed of three membranes (2 systems)
    • possesses its own DNA and ribosomes
    • a kind of plastid ... others include chromoplasts (pigments) and amyloplasts (starch)
  33. Mitochondria and bacteria are ....
    similar in size
Author
clintave
ID
131399
Card Set
Biology 172 Lecture 9
Description
Biology 172 Lecture 9 exam review
Updated