C, H, O, N, P, Ca & S. Make up 97% of the human body.
B, F, AL, Si, V, Cr. Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br Mo, Cd, W and I may also be present
4.6 bill yrs. ago when earth was formed till ~3.5 bill yrs ago
Oparin & Haldane
Early earth atmosphere probs contained small simpe compound (H20, N2, Co2) and then uv radiation or lightning cause these to react to make simple organic compounds.
Miller and Urey
replicated this and showed that H20, Ch4, NH3 and H2 with electric discharge resulted in water soluble org compounds, including amino acids
Hydrothermal vent hypothesis
Argues that biomolecules first generated in ocean floor near hydrothermal vents which emit metal sulfides at very high temps.
rxtive portions of molecules
chains made up of repeating units linked end-to-end
Lose h20, join
Add water, split
how biomolecules became more complex. began adding other small molecules, gaining functionality.
macromolecules can assoc with eachh other where functional groups are complementary. Specific pairing allows one member to rec. the other group and its orientation.
Is enabled by complementarity. it allows a macrmolecule to direct thhe assembly of a new molecule from smaller complementary units.
NH2, R2N, R3N
RSH (sulfhydryl group)
R-C-O-O-H carboxyl group
or R-C-O-O -. carboxylate group
C-O-O- (ester linkage, w/carbonyl)
R-C-O- (acyl group)
thoester linkage, acyl group
C-O-N amido group
R=NH or R=N (etc)
C=N imino group
see pg. 4
may have happened due to vesicles' enclosure of self-replicating biomolecules. advantageous because it maintain hhigh concentrations of stuff that would otherwise diffuse away.
Organisms that could manufacture necessary molecules from more readily available precursors were favored by evolution
Photosynthesis allowed cells to make use of energy source, as o2 accumulated, organisms faced pressure to avoid oxidative damage-->developed aerobic respiration, taking advantage of o2 levels
have a nucleus. tons of organelles. multicellular frequently, morphologicaly complex.
no nucleus (archea and eubacteria). simple, mostly unicellular, but fill very diverse niches.most numerous and widespread.
need host to replicate
cocci, bacilli, spirilla
extremohiles (methanogens, thermophiles, halophiles)
Endosymbiosis theory. Bacteria (mito and chloros) formed symbiotic relationships with eukaryotic cells.
changes in individs genetic makeup arise at random, but if they confer a survival advantage increases likelihood that will be passed on to the nextgen
study of energy and its effects on matter
System + surroundings
part of te universe that is of interest. surroundings is everything outside system. in sum, universe.
1st law of thermodynamics
Energy is conserved, but if system undergoes a change, soem energy can be used to do work.
H. delta H = change in heat. Energy change of a system is equivalent to enthalpy change!
occurs without energy input from outside system. characterized by the conversion of order to disorder
2nd law of thermodynamics
energy tends to increase
number of ways to arrange system components in energetically equivalent ways (W)
entropy. =kb *lnW
where kb is botlzmann constant
Delta S system + Delta S surroundings
make positive delta S universe
To be spontaneous..
Delta H-TdeltaS=delta G <0
driven by energy input (not spontaneous)
At eq, delta G=
thermodyamic msrmnnnnts can be made only considering 1st and final states. (allows experimental msrmnt of stuff)
entropy and free energy vary w/ concentration.
Delta G = sum of..
free energies of proudcts, minus free energies of rxtants
Delta G standard state=
25 C, 1 atm, activity of 1
Closed vs. open systems
Closed systems can't exchange matter or energy with environment, while open can. Closed will come to equilibrium, but open will not. Organisms therefore do not come to an equilibrium (till death)
orgs exist suchh that all flows in the system are so constant that the system does not change with time
biological catalysts. mostly proteins. accelerate biochem rxns by physically interacting with rxtants and products to give a mroe favorable pathway for the transformation from one to the other