Metabolism 1 & 2 Flashcards
What is the sum of all chemical reactions that can occur in a living organism?
Metabolism
What is the term used for biosynthetic pathways? Energy producing pathways?
Anabolic / Catabolic
What is the energy currency of the body?
ATP
What does ATP derive its energy from?
Phosphoanhydride Bonds (resonance, repulsion, entropy)
What is another form of energy in vivo? (hint, reducing equivalent)
NADH / FADH2
As a rx. Has a more negative gibbs free energy it is?
More Favorable / more spontaneous
(?:247) What organelle consumes the most oxygen in vivo?
Mitochondria
Each rx. In metabolic pathway is ____________ _____ ___ _____________?
Catalyzed by an enzyme
The product of one rx. In a pathway is the _______ for the next rx. In the same pathway.
Substrate
T or F: pathways can be reversible
F, but some individual steps may be
What is the first irreversible step in a pathway called?
Rate Limiting Step
What is the first irreversible step in a pathway called?
Commitment Step
What are two ways to control pathways?
Regulate enzymatic activity, or amount of enzyme, or both
As the energy charge increase what also increases?
ATP Utilization Pathways
What are the three stages of metabolism?
Breakdown of macromolecules to monomers; oxidation of monomers to acetylCoa with limited ATP formation; complete aerobic oxidation of Acetyl-CoA to carbon dioxide and water (he means glycolysis here followed by TCA, in turn with pyruvate DH complex catalyzation followed by ETC in the end for ox phosphorylation)
What are the two reducing equivalents used most frequently in glycolysis/TCA for energy production (hint: has adenine as part of structure)
NADH, FADH2
What do the molecules (NADH FADH2) contribute to across the mitochondrial membrane?
Electrochemical gradient
T or F: A positive dE yields a nonspontaneous reaction
F, Recall: dG=-nJE
What pathway is used to make ethanol via bacteria?
Fermentation, via alcohol dehydrogenase, etc.
What does lack of NADH in glycolysis produce?
Lactic Acid
Does most of our energy come from glycolysis?
No, from TCA/ETC
What is the primary fuel for body metabolism?
Glucose
What is an example of another fuel we use when glucose is not available?
Ketone Bodies
What contains most of the energy stores in normal human individuals?
Fat, followed by protein, glycogen, and then glucose
Name 4 anabolic pathways discussed in lecture
Gluconeogenesis, glycogenesis, protein synthesis, lipogenesis
Name 4 catabolic pathways discussed in lecture
Glycolysis, TCA/ETC, proteolysis, lipolysi, glycogenolysis, pentose phosphate pathway
What is the significance of the pentose phosphate pathway?
Produces pentoses needed for nucleotides and reducing equivalents to counter oxidative damage (NADPH)
What happens in the “fed state”?
Storage, synthesis, oxidation
Can RBC’s undergo oxidative phosphorylation?
No, they have no mitochondria
In the liver, what enzyme activates glucose to glucose-6 phosphate?
Hexokinase IV
What can form to make ketone bodies?
Acetyl coa + acetate beta-hydroxybutyrate
Describe ATP synthesizing pathways
Energy released by oxidative catabolic rxns used to synthesize ATP and other high energy cmpds, which ATP utilizing rxns, including anabolic rxns
What are processes that use ATP?
motion, active transport, biosynthesis, signal amplification
How can ATP be converted to AMP?
2 high energy phosphates are used to form AMP and pyrophosphate yielding 2 inactive P which will drive the rxn further
Which foodstuff will produce urea along with energy?
protein
If you increase the amount of -delta G from high energy bonds thus increasing the neg kCal will push the reaction in which direction?
More of the rxn will lie toward the products
T/F All pathways are linked, and all pathways are regulated
True
How are the pathways linked?
linked through the substrates and is used WRT availability
T/F Every step in pathways are irreversible
False, at least one pathway is irreversible so the pathway itself is reversible but many steps may be reversible or irreversible
How are all pathways controlled?
the slowest step which is the rate limiting step that is usually a REGULATORY ENZYME and IRREVERSIBLE
What are the types of metabolic pathways? Describe each of them
Linear=> one substrate -> one product
Branched=> multiple products
Cyclic pathways => pathways starts and ends with same cmpd (molecules enter/leave cycle)
Cascade/amplification pathways => signal transduction, blood clotting
What are 2 ways in which the enzymes and metabolic pathways are regulated or controlled?
allosteric control / feedback inhibition (bind to sites other than active sites)
Reversible covalent modification (phosphorylation)
What gives each tissue its own unique metabolism?
regulating proteins will cause use of different sets of functional proteins
What are regulators that recognize how much energy change is present within the cell?
ATP and AMP levels (ATP generating=> catabolic) (ATP-utilizing=>anabolic)
More energy change then more ATP used
