energy
The ability to do work or cause change
examples of different forms of energy
-chemical -mechanical -thermal -electrical -kinetic -potential (stored energy)
free energy
the energy available in a system for work
chemical equations
represent chemical reactions
reactants and products
-reactants are shown on left side of the equation, products on the right. -in reactions the amount of product must equal the amount of reactants
Equilibrium
reached when both the reactants and products are made at the same rate
bond energy
the energy needed to break a bond between two atoms
where does most of an organism's energy come from?
sugar in foods
exothermic/exergonic reactions
release more energy than it absorbs
endergonic/endothermic reactions
store energy
what are most reactions in cells?
endergonic
activation energy
energy needed to start a reaction
catalysts
-lower the amount of activation energy needed -called enzymes, and are usually proteins -often end with suffix '-ase'
properties of enzymes
-they speed up a reaction by lowering the activation energy -very specific -proteins -may work on 1 or 2 substrates at the most -reusable -work by induced fit -adversely effected by temperature
define solution
a mixture in which 2 or more substrates are uniformly distributed in another substance.
solute
is dissolved in the solvent in a solution
water
the universal solvent
When does a solution become saturated?
when no more solute will dissolve
aqueous solutions
have water as the solvent & are important to LIFE
denature
when enzymes come apart & can no longer function