Flashcards in Lecture 1&2: Kincaid Deck (37)
Sharing of a pair of electrons
A charged group can attract an oppositely charged group
Hydrogen atom covalently bonded to one EN atom is also attracted to another
Van dear walls interactions
Results from the asymmetrical distribution of electrons in molecules or atoms
Common COVALENT c-c bond distance and energy:
1.54 angstroms; 355 kJ mol-1 (85kcal)
Common electrostatic interaction length
3 angstroms; 5.86 kJmol-1
Common hydrogen bond length
1.5 -2.6 angstrom; 4-20 kJ mol-1
How to combine sugar and amino acid moieties:
Which carbon in DNA is "deoxy"
Sugar+nitrogenous base(NO phosphate group)
Adenine and thymine have___ bonds; Guanine and cytosine have ____ bonds.
Properties of water:
Polarity, cohesion, moderation of temperature, expansion upon freezing, versatility as a solvent
Nonpolar to cluster together to exclude water in aq. Environment
Guanine: pKa =9.7 what's this mean?
Above this pH, you lose H's...DNA becomes single stranded
Protonated = deprotonated
The susceptibility of proton removal
PH is lower than pKa:
Hydrogen bonds remain intact
Regulate pH in organisms and in lab; weak acid and its conjugate base
Buffers are most effective at pH:
near their pKa
Rate of the forward reaction = rate of reverse; [ ] of R / P don't have to be =
Release energy by breaking bonds of complex molecules to simpler.
Consume energy to build complex molecules from simpler ones.
Asso. W/ motion
Also. W/ random movements of atoms/molecules
Energy in matter that is present d/t location or structure
First law thermodynamics
Total energy of a system and environment is constant. "Can't be created or destroyed"
Second law thermodynamics
Entropy of system and environment always increases. Spreading
IF disorder increases, why does an organized DNA helix form?
The heat released by helix formation increases the entropy of the surrounding.
A living organisms energy that can do work