bio quiz 11/4

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