Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
53 Cards in this Set
- Front
- Back
Dr. Peters Studies |
Terpinoids |
|
What is the primary metabolic fate of acetyl-CoA entering the TCA cycle |
Used to produce ATP |
|
What molocules are formed by hydrolysis of CoA thioesters in the TCA cycle? |
Citrate and CoA Hydrolysis of citryl CoA thoeester to citrate and CoA drives the overall reaction far in the direction of synthesis of citrate |
|
Why is oxidation of tertiary carbon not desirable in the TCA? |
Tertiary alcohols cannot be oxidized. Secondary alcohols can be oxidized. |
|
Which enzyme is a direct link between the TCA cycle and electron transport chain? |
Succinate Dehydrogenase |
|
What type of oxidation provides less energetic electrons? |
Less: FADH2 - oxidation of succinate - 1.5 ATP More: NADH - oxidation of malate - 2.5 ATP |
|
Whare are succinate dehydrogenase,fumarase and malate dehydrogenase not heavily regulated? |
The regenerate precursors, which must be present for reactions to occur to produce oxylacetate. oxylacetate begins and ends the TCA cycle so must be present. |
|
What is the primary product of glyoxylate? |
Succinate which can be used and synthesize glucose. |
|
What type of co-factors carry electrons in the electron transport chain? |
Prominent electron carriers (Porpherins) or Heme groups |
|
At what complex/enzyme do electrons from FADH2 enter the electron transport chain? |
Complex II - Succinate dehydrogenase or succinate-Q reductace and through complexes II and IV |
|
What organelle is particularly important in generating cellular energy? |
Mitochondria |
|
What complexex in the electron transport chain do (not) pump electrons? |
Complex II does not pump electrons Complex I, III, IV pump electrons |
|
Which stat of ubiquinone (co-enzyme Q) is particularly important for proton pumping by Complex II? |
Semiquinone radical anion |
|
How many protons are pumped per electron by complex IV? How many protons are pumped per water formed by complex IV? |
1 proton per electron 2 protons per water formed |
|
How is the electron transport chain regulated? |
Citric acid cycle, Q pool Concentration gradients/ production of NADPH and FADH2 |
|
Why is the electron transport chain dangerous? |
Reduction of O2 can result in dangerous side reactions, partial reduction to generate hazardous compounds. In particular, the transfer of a single electron to O2 forms superoxide ion, whereas the transfer of two electrons yields peroxide. |
|
In tissues where the malate-aspartate rather than glycerol-3-phosphate shuttle is used for cytoplasmic NADH what is the change in number of ATP formed per glucose? |
Glycerol-3-phosphate is less efficient - look at tale 21.1 or 20. |
|
What is the key aspect of the "c" subunit for ATP synthase function? |
Drives production of ATP by moving. Moves by protein gradient. |
|
What dirves import of ATP in the mitochondrial matrix? |
Proton gradient coupled with ADP Eversion process. ADP from outside matrix induces conformational change. |
|
How many protons must go through ATP synthesis to produce 1 ATP if there are 9 subunits in the "c" ring? |
More C subunits longer it will take with 9 units 360/9 means 40 degrees fro each unit. to go to 120 degrees 3 protons must go through. Production of ATP per 120 degrees of rotation. |
|
How many more ATP are formed via electron transport and oxidative phosphorylation form NADH than FADH2? |
23 ATP from NADH 3 ATP from FADH2 20 more more ATP |
|
If and ATP synthase with 9 subunits in it's c-ring has a minimum pH for activity of 1.1 units, would the pH for activity for the ATP synthase with 12 subunits in the c-ring be more or less than 1.1? |
More subunits would require a higher concentration of protons. pH would be more than 1.1 |
|
Why are the certain photosynthetic microorganisms not green? |
Different light absorbing compounds that absorb green light instead of reflect it. Plants don't absorb green light an reflect it. Structural changes can affect light absorption. |
|
What is the key function of cytochrome bf in photosynthesis? |
Membrane bound proton pump between photosystem I and II. Accepts electrons and protons from one side and drops them off tho the other side. Carries out the Q cycle |
|
What is the key difference between the proton motive force on chloroplasts vs. in mitochondrion? |
Water --> oxygen NADP+ --> NADPH Chloroplasts only use protons. Mitochondria use other ions as well. |
|
What process underlines transfer of energy from carotenoids to chlorophyll? |
Funneling of electrons to reaction center. All done via resonance energy. Electrons of higher energy going to lower energy. |
|
Generally, NAD+ is used for _______, while NADPH is used for ________. |
NADPH usually used in anabolism(synthesus) NAD+ Usually used in metabolism(breaking down) |
|
Are all photosynthetic organism oxygenic? |
No but it is more effective. See table 22.1 |
|
How do plants defend themselves? |
Can produce varios molocules. Usually terpenoid derived. We use some of these molocules (caffiene aspirin) |
|
What is a key similarity betwen thylakoid and mitochondrial inter membranes? |
They both have Q pools and inolved with proton gradient ATP synthase. |
|
Which enzyme fixes CO2/transfers carbons between sugars/splices sugars together. |
Rubisco - fixes Transketolase - transfers carbons Aldalase - splices sugars together |
|
What drives the fixation of CO1 in phosphotrioses? |
Reduction of one carbon with oxidation of another |
|
What is a key difference between reduction in gluconeogenesis and calvin cycle? |
Gluconeogenesis uses NADPH instead of NADH |
|
How is the Rubisco activaton by the action of photosystem II ( proton gradient)? |
Transfer of electrons instigated by light transferring. Thioredoction activates/reglates enzymes, one being Rubisco. |
|
What is the difference between the activated glucose destined for starch verse sucrose anabolism? |
Uracil vs. adenine Startch(ADP) Sucrose(UDP) (these are the same thing) |
|
What compound is key to the CO2 concentration mechanism of all C4 plants? |
Oxaloacetate carries CO2 from meophyll to cells on surfaces of leaves to interior bundle-sheath cells, which are the major sites of photosynthesis. Pohonial ryruvate - binds CO2 tto become oxaloacetate. Malate easily transported accross membrandes (TA says malate is the best answer.) |
|
How do tropical C4 plants separate capture of CO2 from its fixation? |
Tropical - separate spatially(space) from the carbon cycle extra: Desert temporally(time) separated |
|
Why is glycogen more highly branched than starch? |
We can degrade glyocogen more quickly since we require energy to move. Plants don't so they use starch and give off oxygen. |
|
What chemical is used to cleave the 1,4-glycosidic bonds of glycogen? |
Phosphorylase (1:10 ratio of 1,6 bonds to 1,4 bonds) |
|
Wha is required to access the 1,6-glycosidic branch points of glycogen? |
Transferase a - 1,6-glucosidase - creates a free molocue of glucose. Requires ATP to enter hexose monophosphate pool. |
|
How many ATP are required to produce 100 hexose monophosphates from glycogen? |
10 ATP - dependent on 1:10 ration of 1,6 to 1,4 |
|
What is the difference between the a and b states of phosphorylase differ from that of muscle phosphorylase? |
Liver- largely regulated by excess free glucose Liver is a glucose source organ Muscle - largely regulated by need for ATP Muscle is a glucose sink organ |
|
What is the effect of the adrenaline and of muscle phosphorylase? |
Adrenaline - intergrated metabolic response (activates Phosphorylase A) Insulin - shut off Phosphorylase / inactivates it Glucagon - activates Phosphorylase A in liver Insulin - inactivate Phosphorylase A in the liver |
|
Why is glycogen more highly branched than starch? |
Starch is long linear chains being branched allows the glycogen to be use more quickly than starch and enables fast construction. Regulations balances construction/destruction |
|
What kind of enzyme is involved in both degradation and construction of glycogen? |
Transferases are invovled |
|
What is required to construct the 1,6-glycosidic branch points of glycogen? |
Minimum of 4 glucose chain, UDP-glucose, transferase (branching enzyme) Synthase extends both nonreducing ends followed by branching/ |
|
How many ATP are required to incorporate 10 glucoses in glycogen? |
2 ATP/glucose glycogen therefore 20 ATP |
|
Which enzyme is activated by insulin? |
Glycogen synthase (?check) it deactivates glycogen synthase kinase (check?) |
|
Why is it important that there is an excess of phosphoyrlase PP1? |
To allow synthesis of glycogen from b to a We don't want activation of glycogen synthase, inefficient to always be producing glycogen. Phosphorylase regulates PP1 so keep it tightly regulated. |
|
Which proteins inhibit the activity of PP? |
Protein kinase A Phosphorylase A also regulates it |
|
Why might glucose 6-phospate be converted to ribose 5- phosphate? |
Source of nucleotides (nucleic acid precursor) to make DNA (oxidation reaction) Dividing cells and production of DNA |
|
What kind of enzyme is involved in both the Calvin cycle and Pentose Phosphate Pathway? |
Transketolase/transaldolase therefore transferees is involved |
|
How can the Pentose Phosphate Pathway be use to generate both NADPH and ATP? |
In the process of making Ribulose 2 molocule |