Chemistry
Covalent atoms ___ pairs of valence electrons
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What is the monomer of a lipid?
Trick question-- there is none :)
lipids are NOT composed of repeating subunits (diverse class of macromolecules)
What is responsible for the difference in charge, polarity, and size of proteins?
R group properties
Describe the first 2 laws of thermodynamics
1) energy is neither created nor destroyed; it is transferred
2) transformation of energy is associated w/ INCREASE in DISorder (entropy)
Free energy: energy that can be used to ___ ____
HIGH free energy: ___ stable, ___ concentrated, ____ ordered, ____ work capacity,
DO WORK!
less stable; more concentrated, more ordered, greater work capacity
Atoms are MOST stable when...
each orbital has 2 electrons
What are the monomers of...
-proteins, carbohydrates, & nucleic acids
proteins = amino acids; carbs = monosaccharides; NA = nucleotides
POLAR R-groups are ____, form ____ bonds, and _____ dissolve in water
hydrophilic; hydrogen bonds; readily
A protein is ___ ordered, but ____ stable than its amino acid subunits
more; less
Name 3 things that affect the rate of a rxn
2) enzyme conc
3) temperature
4) pH (+ concentration of other ions)
Which type of bond is most likely to be formed in a single water molecule? Which type of bond is most likely to be formed between two water molecules?
within: polar covalent
between: H-bond
Draw the generic structure of a protein
C attached to... NH2 (amino), Carboxyl (COOH), R group, & H
What type of bond is created to form a protein? Which parts of the protein link to form this bond?
1) peptide bond
2) amino end and carboxyl end attach
TRUE OR FALSE: catalysts lower the delta G of the rxn by being consumed in the rxm
FALSE! catalysts LOWER activation energy & are NOT consumed in the rxn (G unchanged)
When is Vmax reached?
Vmax reached when enzyme is processing substrate to product as fast as POSSIBLE (saturation)
Which type of interactions are critical for protein folding + membrane structure? What is an example?
HYDROPHOBIC interactions, non polar (van der waals forces)
Polymers are formed from monomers through what type of reaction?
Condensation (dehydration) reaction-- LOSS of H2O; covalent bonds are formed
What are the 3 determinants of protein structure?
2) cell environment (temp, salt/ions, pH)
3)presence of folding aids (chaperone proteins, which assist in folding other proteins)
TRUE OR FALSE: Enzymes can only catalyze reactions that have a negative G
true; must be coupled so overall G is negative
What is Km? What does a small Km value mean? What type of affinity will an enzyme have for a small Km?
Km = substrate concentration at which the reaction rate is half maximum
low km= enzyme achieves max catalytic efficiency at low substrate concentrations; aka VERY EFFICIENT catalyst/good substrate
enzyme has HIGH affinity for substrate with low Km
Name the 6 carbon functional groups + provide their structures
1) amino (NH2)
2) carbonyl (C=O(+-H))
3) carboxyl (COOH)
4) hydroxyl (OH)
5) phosphate (PO4)
6) Sulfhydryl (SH)
Name & describe the interactions present within the 4 types of protein structure
1) primary-- linear sequenze of amino acid; DICTATES protein folding (determine protein function)
2) secondary--held together by hydrogen bonds, which form alpha + beta helices
3) tertiary--SINGLE polypeptide chain with 1+ secondary structures; overall 3D shape of polypeptide formed; held together by via H-bonds, van der waals, covalent, + ionic bonds
4) quaternary--MORE than ONE polypeptide chain interacting to form single structure; held together by covalent, ionic, hydrogen, and/or van der waals
-Enzyme + substrate --> enzyme-substrate complex--> change in substrate --> products + release
Name & describe the two types of reversible enzyme inhibitors
1) competitive: SIMILAR to substrate; competes with substate for active site; adding substrate CAN overcome inhibition
2) non-competitive: NOT similar to substrate; do NOT bind at enzyme's active site; addition of substrate will NOT overcome inhibition