Test 2 Intro to Metabolism Flashcards
Catabolism
The breakdown of complex molecules into their smaller components
Anabolism
The synthesis of complex molecules from their simpler subunits
True or False: Anabolic pathways are typically endergonic
True
Energy
1.Capacity to do work
2. Cause change
What are two units of energy?
Joules and calories
What are the three kinds of work?
Chemical, Transport, and mechanical
Thermodynamics
The study of energy change in a system
First law of thermodynamics
The law of conservation; states that energy can neither be created nor destroyed, and that it can only be transformed or redistributed
Second law of thermodynamics
State that entropy (or disorder) in the universe is always increasing
Exergonic reactions
Reactions that release energy and have a negative DG
Endergonic reactions
Reactions that consume energy and have a positive DG
Energy coupling
Occurs when energy released from an exergonic reaction is used to fuel an endergonic reaction.
High-energy compound
1.Compound with excess energy
2. Used to drive reactions.
Oxidation
The loss of an electron.
Reduction
The gain of an electron
In a redox reaction, the electron donor is _________ and the electron accept is _________
oxidized; reduced
Cellular respiration is a redox reaction in which glucose is (reduced/oxidized)
Oxidized
Equilibrium constant for an oxidation-reduction reaction (E0)
The measure of a reducing agent’s tendency to lose electrons. (Also called the standard reduction potential.)
A compound with a more negative E0 is a better electron ______, while a compound with a more positive E0 is a better electron _________.
donor; acceptor
What are some examples of electron carriers?
FAD+, NAD+, NADP+, cytochromes and coenzyme Q
True or false: ATP and ADP are electron carriers
False
Enzyme
A biological catalyst that speeds up the rate of reaction by lowering the activation energy–the energy needed for the reaction to proceed through its high-energy transition state.
Holoenzyme
The protein component of an enzyme (i.e., the apoenzyme) and the nonprotein component (i.e., the cofactor).
Apoenzyme
The protein component of an enzyme
Cofactor
1.The nonprotein component of an enzyme
2.Acts as a coenzyme or as a prosthetic group that is firmly attached to the enzyme.
What are three factors that impact enzymatic activity?
1.pH
2.Temperature
3.substrate concentration
Denaturation
Protein’s structure and function altered due to change from optimal temperature or pH levels
Competitive inhibitors
Molecules that attach to the enzyme’s active site, prevent the substrate from binding.
Noncompetitive inhibitors
Molecules that attach somewhere other than the enzyme’s active site, changing the enzyme’s shape and preventing the active site from accepting the substrate molecule.
Feedback inhibition
1.When the end product of a metabolic pathway acts as a noncompetitive inhibitor for an enzyme in the metabolic pathway,
2. Shuts down pathway when enough of the end product is produced.
