Catabolism
Breakdown pathways - breaking down of complex molecules to simpler compounds
IE: Cellular respiration
Metabolism
An emergent property of life.
The totality of all an organism's chemical reactions
*It is never at equilibrium. If it were, we'd be dead
Anabolism
consume energy to build complicated pathways from simpler ones.
IE: synthesis of protein from an amino acid
dehydration reaction
a chemical reaction in which 2 molecules become covalently bonded to each other with the removal of a water molecule
metabolic pathway
begins with a specific product and ends with a product.
It is catalyzed by a specific enzyme @ each step
synthesis reaction
a type of chemical reaction in which two or more simple substances combine to form a more complex product
catalyst
chemical agent that speeds up a reaction without being consumed by the reaction
Exergonic Reaction
Energy is released in the reaction.
Delta G is (-).
Occurs spontaneously if energetically favorable.
Endergonic Reaction
Energy is absorbed from surroundings
Delta G is (+)
Non Spontaneous reaction
Spontaneous Reaction
Reactions that are going to happen anyway. Like water falling downhill. Does NOT mean quickly!!
Goes without an input of energy
Nonspontaneous Reaction
process that leads to a decrease in energy. Like water being pumped uphill.
Entropy
measure of disorder or randomness in the universe
enzymes
is a catalytic protein. Speed up metabolic reactions that would happen anyways by lowering energy barriers. Enzymes end in -ase
DO NOT affect the change in free energy (Delta G)
Feedback Inhibition
the end product of a metabolic pathway shuts down the pathway.
Prevents a cell from wasting chemical resources by synthesizing more product than is needed.
Allosteric Inhibition
stabilizes the inactive form of an enzyme
cooperative inhibition
form of allosteric regulation that can amplify enzyme activity
noncooperative inhibition
the inhibitors exert their effects independently.
free energy
Energy that can do work when temperature and pressure are uniform as in a living cell.
(-) Delta G is Spontaneous
change in free energy formula
Delta G = Delta H - T(Delta S)
Delta H = total energy
Delta S = change in entropy
T = temperature in Kelvin
Enthalpy
is the amount of heat content used or released in a system at constant pressure.
substrate
reactant that an enzyme acts on
active site
region on the enzyme where the substrate binds
cofactors
nonprotein enzyme helpers
Coenzyme
organic cofactors. Vitamins
Proton Motive Force
generated by an electron transport chain which acts as a proton pump, using the energy of electrons from an electron carrier (Gibbs free energy of redox reactions) to pump protons (hydrogen ions) out across the membrane, separating the charge across the membrane.
autotrophs
organisms capable of generating their own food. IE: Plants
Use photosynthesis or chemosynthesis
*Producers!
heterotrophs
obtain all of their organic material from other organisms.
IE: Animals, fungi
*Consumers of the biosphere
substrate level phosphorylation
ATP made by direct transfer of a phosphate group from an organic substrate and ADP by an enzyme
oxidative phosphorylation
Electron transport & chemiosmosis. Produces 90% of ATP in cellular respiration. Powered by Redox Reactions
alkaline
pH greater than 7
1st Law of Thermodynamics
Energy cannot be created nor destroyed
2nd Law of Thermodynamics
Every energy transfer or transformation increases the entropy of the universe.
*Ergo, heat is disorganized form of energy
Oxidation
removing electrons
reduction
addition of electrons
Purpose of Oxygen in Cellular Respiration
Final Electron Acceptor