MICRO EXAM #2b – Flashcards
Unlock all answers in this set
Unlock answers| What is potential energy? |
| -stored energy -water behind a dam |
| What is kinetic energy? |
| -energy of motion -free energy available to do work -movement of water from behind a dam |
| What is catabolism? |
| -biodegradation -energy-releasing processes -breakdown of compounds in order to produce ATP |
| What is anabolism? |
| -biosynthesis -energy-consuming processes -utilize stored energy to synthesize macromolecules |
| What are the 3 types of metabolic pathways? |
| -linear -branched -cyclical |
| Is ATP formed or used in catabolism/anabolism? |
| -ATP are made in catabolism -ATP are used in anabolism |
| What are the characteristics and functions of enzymes? |
| -enzymes are biologically active proteins -produced from genes w/in DNA -are catalysts -can be recycled -end in "-ase" |
| How do enzymes speed up chemical reactions? |
| they lower the activation energy -strain on the bond lowers activation energy |
| What is induced fit? |
| enzymes bind their substrates at the active site -active site molded to fit substrate -lock & key shape |
| What factors can affect enzyme activity? |
| -temperature -pH -salt concentration (low) |
| What are coenzymes? |
| non-protein, organic/inorganic compounds (tend to be small molecules) |
| What are cofactors? |
| -organic -come & go -carry/shuttle ATP |
| What are the 2 types of enzyme inhibition? |
Competitive -blocks correct substrate from binding -usually permanent
Noncompetitive/allosteric -inhibitor binds to allosteric site -changes shape & temp. prevents substrate from binding -indirectly block active site |
| What is feedback inhibition? |
a form of allosteric inhibition
-when end product binds to active site of 1st enzyme in a pathway -allows pathways to self-regulate |
| Why is ATP a high-energy molecule? |
-fuels enzymatic reactions -energy currency of the cell -energy is stored in the chemical bonds between the phosphate groups -energy to produce ATP comes from catabolic metabolism of organic molecules |
| What is oxidation? |
the loss of electrons, release energy
(LEO) |
| What is reduction? |
the gain of electrons, gain energy
(GER) |
| What are the 2 primary electron carriers and what is their job? |
NAD+ (oxidized) NADH (reduced) &
FAD (oxidized) FADH2 (reduced)
-they are electron "taxis" |
| What are precursor metabolites? |
intermediate products produced in catabolic pathways that are used in anabolic pathways
-serve as carbon skeleton for building macromolecules |
| What is glycolysis? |
-10 step oxidation of glucose into 2 pyruvate
-generates ATP & NADH -net gain of 2 ATP (sub. level phosph.) -net gain of 2 NADH (from redox rxns)
-produces 6 different precursor metabolites
-functions with or without oxygen |
| What happens in the preparatory stage of glycolysis? |
|
| What happens in the pay-off stage of glycolysis? |
|
| What is substrate phosphorylation? |
| ATP using chemical energy to add phosphate ion to ADP |
| How does the Pentose Phosphate Pathway (PPP) contribute to glycolysis? |
|
| Wht is formed in the transition step? |
|
| What is formed, per glucose, in the Krebs cycle? Are there precursor metabolites? |
Yes |
| What is the Electron Transport Chain? |
| a series of membrane-bound carrier molecules that are oxidized and reduced as e- are passed down the chain to terminal e- acceptor |
| Where is the ETC located in bacterial cells? |
| cytoplasmic membrane |
| What is a Proton Motive Force? |
Protons (H+) are pumped from inside the cell to the outside as e- are passed
|
| What is aerobic respiration? |
| final electron acceptor in ETC is molecular O2 |
| What is anaerobic respiration? |
final electron acceptor in ETC is NOT O2
-yields less energy than aerobic resp. |
| What is ATP Synthase and what fuels it? |
creates ATP by transporting H+ back into the cell (Proton Motor vis Chemiosmosis)
|
How much ATP is produced from one glucose molecule through both substrate-level phosphorylation and oxidative phosphorylation? |
AEROBIC Glycolysis = 2 ATP (sp) TCA Cycle = 2 ATP (sp) ETC = 34 ATP (ox. phos.) Total = 38 ATP ANAEROBIC Glycolysis = 2 ATP (sp) Partial TCA & ETC = 30 ATP (ox. phos.) Total = 32 ATP |
| Why do organisms use fermentation? |
|
| What is the substitute terminal electron acceptor of fermentation? |
| pyruvate or another organic molecule |
| What group/type of enzymes are necessary for breaking down macromolecules? |
| Hydrolytic enzymes |
| What is photosynthesis? |
| harvesting energy from sunlight to make ATP and sugar; and fix CO2 |
| Chemolithotrophs |
| utilize inorganic compounds as energy source for ETC |
| What purpose do anabolic pathways serve and what are their substrates? |
| they synthesize macromolecules |
