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2011-01-27 11:19:45
cell bio test1 ch1 ch2 ch4

test 1 material - ch. 1,2,4
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  1. What are the four levels of protein structure?
    • primary: amino acid sequence
    • secondary: alpha helix or beta sheet
    • tertiary: 3-D formation of protein chain
    • quaternary: interaction between multiple proteins
  2. Who first discovered the cell?
    Robert Hooke
  3. Who was first to observe a living cell?
    Antoni van Leeuwenhoek
  4. What are the three tenets of cell theory?
    • 1. all living organisms are made up of one or more cells
    • 2. Cells are the basic unit of life
    • 3. All cells arise from preexisting cells
  5. What are some advantages of multicellularity?
    • cells can specialize, allowing for more efficiency and diversity
    • organisms can grow larger, allowing for better predation
  6. What some features of a model organism?
    • the organism can reproduce rapidly
    • can be bred in a laboratory environment
    • can be genetically manipulated
  7. List the noncovalent interactions that underlie protein folding and where they occur.
    • Electrostatic interactions: r-groups in amino acids
    • hydrogen bonds: bind amino acid side chains
    • Van der Waal forces: binding in the close folds of the protein
    • hydrophobic interactions: hydrophobic portions of the protein are folded inside, and hydrophilic regions are outside
  8. Define ligand.
    An entity that is bound by a protein.
  9. Define proteasome.
    An organelle that will unfold and cleave proteins in a cell.
  10. What is an enzyme?
    A protein that binds to a substrate and converts them into a chemically modified product.
  11. What the three main ways an enzyme encourages catalysis?
    • An enzyme can bind to two substrates and align them to encourage a reaction
    • An enzyme can bind to a substrate and rearrange electrons in the substrate to create partial charges that favor a reaction.
    • An enzyme can strain (bend) a bound substrate to force a transition state that favors a reaction.
  12. How does a lysosome function?
    The lysosome binds to a polysaccharide chain in a bacteria's cell membrane, bends it, add a water molecule, causing it to break. This will cause the cell membrane to rupture.
  13. What are four major classes of organic molecules in cells?
    What are the building blocks for these molecules?
    • polysaccharides: sugars/monosaccharides
    • lipids: fatty acids
    • proteins: amino acids
    • nucleic acids: nucleotides
  14. What are the four nucleotides present in DNA?
    • adenine
    • thymidine
    • guanosine
    • cytidine
  15. Which nucleotides are purines, and what is their structure?
    Adenine and guanosine, structure is double-ring.
  16. Which nucleotides are pyrimidines, and what is their structure?
    Thymidine, cytidine, and uracil, structure is a single ring.
  17. What the nucleotide pairs?
    • A-T
    • C-G
    • (A-U)
  18. Describe the amino acid structure.
    • n-terminus (amino group) attached to carbon backbone, attached to c-terminus (carboxyl group). R-group that varies attached to top carbon.