ANSWERS
Metabolism
The totality of an organism's chemical reactions, which occur anytime two or more
atoms, ions, or molecules collide in such a way that they produce a new substance.
Metabolic pathway
Begins with a specific molecule, resulting in a certain product. §Each step is catalyzed
by a specific enzyme.
Catabolic pathways
Some metabolic pathways release energy by breaking down complex molecules to
simpler compound.
Example of a catabolic pathway
Cellular respiration.
Anabolic pathways
Consume energy to build complicated molecules from simpler ones; they are
sometimes called biosynthetic pathways.
Example of an anabolic pathway
Synthesis of an amino acid from simpler molecules and the synthesis of a protein from
amino acids.
Bioenergetics
The study of how energy flows through living organisms.
Energy
The capacity to cause change. Energy exists in various forms, some of which can
perform work. Energy can be converted from one form to another.
Various forms of energy
Kinetic, thermal (i.e., heat), potential and chemical.
Kinetic energy
Energy can be associated with the relative motion of objects; this energy.
Thermal energy
, Kinetic energy associated with the random movement of atoms or molecules.
Potential energy
An object not presently moving may still possess energy. Energy that is not kinetic is
_____ _____. It is energy that matter possesses because of its location or structure.
Chemical energy
A term biologists use to refer to the potential energy available for release in a chemical
reaction.
Thermodynamics
The study of the energy transformations that occur in a collection of matter.
First law of Thermodynamics
Energy can be transferred and transformed, but it cannot be created or destroyed. The
energy of the universe is constant. "Principle of conservation of energy."
Second law of Thermodynamics
Every energy transfer or transformation increases the entropy of the universe. During
every energy transfer or transformation, some energy is unusable and is often lost as
heat. When converting energy from one form to another, the amount of useful energy
decreases.
Entropy
S. A measure of molecular disorder, or randomness.
Spontaneous process
A process can proceed without requiring an input of energy.
Free energy (ΔG)
Portion of a system's energy that can perform work when temperature and pressure are
uniform throughout the system, as in a living cell.
Free energy equation
ΔG = ΔH - ΔTS.
Enthalpy
H. Total energy/heat present.
Absolute temperature
T.
More free energy (Higher G)