Final exam Biochem

• What is biochemistry?


  The study of the chemistry of life processes
• What do biochemical processes involve?

  Large macromolecules (i.e. proteins, nucleic acids) and low-molecular-weight metabolites (i.e. glucose and glycerol)
• What does structure tell us?

  Function
• Do macromolecules differ greatly between domains of life or are they relatively similar?

  Relatively similar
• What makes up DNA? What about structurally?

  DNA is a linear polymer of nucleic acids

  The nucleic acids are made up of deoxyribose sugar, a phosphate group, and a nitrogenous base
• What sugar is in DNA? RNA?

  DNA: Deoxyribose

  RNA: Ribose
• What are the nitrogenous bases in DNA?

  Adenine

  Thymine

  Cytosine

  Guanosine
• What are the nitrogenous bases in RNA?

  Adenine

  Uracil

  Cytosine

  Guanine
• What nitrogenous base is this?

  Adenine

  
• What nitrogenous base is this?

  Cytosine

  
• What nitrogenous base is this?


  Guanosine

  
• What nitrogenous base is this?

  Thymine

  
• Describe DNA's structure? How does DNA bind to another strand?


  A double helix, anti-parallel

  It base pairs with nitrogenous bases
• What pairs with Adenine?

  Thymine
• How many bonds form between Adenine and Thymine?

  2 Hydrogen bonds
• What kind of bonds occur between nitrogenous bases?

  Hydrogen bonds
• What does Guanine bond with?

  Cytosine
• How many bonds occur between Guanine and Cytosine?

  3 Hydrogen Bonds
• What does base pairing allow for?

  Heredity (because of templates)
• What is the central dogma?

  DNA transcribes into RNA, which translates into proteins
• Is complementary DNA strand assembly spontaneous or non-spontaneous?

  Spontaneous
• What kind of bonds can occur between DNA strands?

  Covalent Bonds

  Van der Waals Interactions

  Ionic Bonds

  Hydrogen bonds

  Hydrophobic/Hydrophilic Interactions
• What are covalent bonds?

  Sharing electrons between adjacent atoms
• What is the distance between C-C bonds?

  1.54 angstrom
• What is the distance between C-C resonance bonds? Is this shorter or longer than C-C bonds?


  1.40 angstrom

  Shorter than C-C
• What is the distance between C=O bonds? Is this shorter or longer than C-C bonds?


  1.34 angstrom

  Shorter than C-C
• What are resonance structures?

  An exhibition of multiple structures based on where electrons are shared
• What are ionic interactions?

  Charged groups attract oppositely charged groups
• What is the Coulomb energy equation?


  E= (Kq1q2)/Dr

  (K= proportionality constant; q1q2= Charges of ions; D= dielectric constant; r= distance between 2 atoms)
• If attraction energy/Coulomb energy is negative, what does this mean?

  You need more force to break the bond a part/dissolve
• What are Hydrogen bonds?

  Connections between an electronegative atom and a Hydrogen, bonded to another electronegative atoms
• What are the electronegative atoms that can bind to a Hydrogen in a hydrogen bond?

  Nitrogen

  Oxygen

  Sulfur

  Phosphorus
• What are van der Waals interactions?

  Weak interactions between 2 atoms that are close enough to create transient asymmetry in electron distribution where the neighbors attract one another
• What is van der Waals interactions dependent on?

  Electron fluctuation around atoms and distance
• What aspect of DNA has a lot of van der Waals interactions?

  The nitrogenous bases in DNA are the perfect distance to have vdw interactions
• What aspect of water allows for hydrophilic/hydrophobic interactions?

  Its polarity
• What is the hydrophobic effect?

  Nonpolar molecules in water can be driven together by the hydrophobic effect, which is powered by the increase in entropy of water
• What is the first law of thermodynamics?

  The total energy of a system and its environment is constant
• What is the second law of thermodynamics?

  The total entropy of a system plus that of its surroundings always increases
• What is entropy? What letter symbolizes it?

  The randomness/disorder in an environment/system

  (S)