Metabolism- collection of all biochemical reactions occuring in a cell
Fundamental property of life
- Typically grouped in pathways- necessary chain of events that must happen
- Product of one reaction often the substrate of another
Breakdown- of larger, more-complex molecules into smaller less-complex molecules
- Turn over unneeded molecules
- Generate monomer building blocks to assemble complex molecular structures
Catabolism- releases chemical energy and or building block molecules needed to run other
cellular processes
- Loss of heat keeps mammals warm
Anabolism- synthesis of larger more complex molecules from smaller, less complex molecules
- Requires input of energy
- Ex: formation of phosphodiester or peptide bonds
- Ordered formation of monomers into a specific sequence
Metabolism is anabolism and breakdown happening at the same time
Energy- capacity to cause a change against a force
Kinetic- energy associated with motion of matter
Thermal energy (heat)- amount of kinetic energy in a collection of matter
Potential- energy stores in matter because of its location, molecular form, position
Chemical energy- potential energy stores in chemical structure
- Energy released from structure by forming new bonds with less potential
Thermodynamics- study of energy transformation in a collection of matter
- Study energy flow through a system- whatever is being studied (cell) and surroundings-
anything not in the system (rest of universe)
1st law- energy cannot be created or destroyed
- But it can be transformed or converted from one form to another
- Ex: photosynthesis (light + CO2 + H20 → heat, O2, glucose), no change in energy from
the beginning to end
2nd law- entropy- disorder of the universe can only increase
- Any local decrease in entropy of the system must be “paid for “ by increasing entropy of
the universe
- Efficiency of a process is always <100% some is always lost
- Entropy is not equal to work output
Thermo doesnt state what reactions are
1st and 2nd laws place constraints on the movement of energy through the universe
- Gibbs formalized free energy - (G) portion of energy in our system able to do work
Energy accounting:
- Total energy in system is H (enthalpy)
- Total free energy in system is G
- Total entropy in system is S
- Absolute temperature is T (kelvin)
We care about how these terms change over time