AP BIO UNIT 3 Flashcards
Metabolism
All of the chemical reactions in an organism
Metabolic Pathways
Series of chemical reactions that either build complex molecules or break down complex molecules
Catabolic Pathway
Pathways that release energy by breaking down complex molecules into simpler compounds
Anabolic Pathway
Pathways that consume energy to build complicated molecules from simpler compounds
Energy
The ability to do work
Organisms need energy to…
survive and function. A loss in energy flow results in death.
Kinetic Energy
Energy associated with motion.
Thermal Energy
Energy associated with the movement of atoms or molecules.
Potential Energy
Stored energy.
Chemical Energy
Potential energy available for release in a chemical reaction.
Thermodynamics
The study of energy transformations in matter. These laws apply to the universe as a whole.
1st Law of Thermodynamics
Energy cannot be created or destroyed. Energy CAN be transferred or transformed. (Example: the chemical energy (potential) stored in the nut will be transformed into kinetic energy for the squirrel to climb the tree.)
2nd Law of Thermodynamics
Energy transformation increases the entropy (disorder) of the universe. During energy transfers or transformations, some energy is unusable and often lost as heat. (Example: as the squirrel climbs the tree, some energy is released as heat)
∆G
Change in free energy
∆H
Change in total energy
T
Absolute temperature (K)
∆S
Change in entropy
Law of Thermodynamics Formula
∆G = ∆H - T∆S
Exergonic Reactions
Reactions that release energy (Example: cellular respiration)
Endergonic Reactions
Reactions that absorb energy (Example: photosynthesis)
Mechanical Work
Movement (Example: beating cilia, movement of chromosomes, contraction of muscle cells)
Transport Work
Pumping substances across membranes against spontaneous movement
Chemical Work
Synthesis of molecules (Example: building polymers from monomers)
ATP
(Adenosine Triphosphate) Molecules that organisms use as a source of energy to perform work