Term
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Definition
| the state of higher energy that a substrate must reach to be converted to product - the energy required to achieve this is ACTIVATION ENERGY |
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Term
| practically, how does an enzyme work? |
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Definition
| by reducing the activation energy required to achive transition state |
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Term
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Definition
| region on the enzyme to which the substrate binds |
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Term
| lock-and-key model vs. induced fit |
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Definition
lock-and-key: substrate fits directly into enzyme active site
induced fit: confirmation of both substrate and enzyme are changed by the active site binding; this can reduce AE by putting the substrate physically closer to its transition state |
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Term
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Definition
| when the product of a metabolic pathway inhibits the enzyme that catalyzes its synthesis |
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Term
| allosteric regulation and what is an example of it? |
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Definition
- when small molecules bind to regulatory sites on an enzyme, changing its conformation and keeping it from binding a substrate
feedback inhibition is a kind of allosteric regulation |
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Term
| what process (addition of a molecule) can either inhibit or stimulate the activity of an enzyme? |
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Definition
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Term
| what factors determine the Gibbs free energy of a reaction? |
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Definition
| temperature, concentration of substances, and intrinsic properties of the substances |
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Term
| what are two ways to hydrolyze AMP and what are the products of each? |
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Definition
- hydrolize to ADP
- hydrolize to AMP and pyrophosphate, which is then also hydrolized (this gives off about double the energy) |
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Term
| what are the three major steps to the oxydation of glucose in a cell? |
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Definition
1. glycolosis
2. citric acid cycle
3. oxydative phosphorylation |
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Term
| what is the purpose of the bumps (cristae) on the inner membrane of the mitochondria? |
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Definition
| they increase the surface area. because this is where ATP is produced, it increases the amount of ATP made. |
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Term
| what are the two ways to generate energy/ATP? |
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Definition
| cellular respiration (breaking down macromolecules in the mitochondria), and photosynthesis (changing carbon dioxide into organic molecules in the chloroplasts) |
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Term
| what essentially happens in cellular respiration? |
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Definition
| glucose is oxydized to carbon dioxide; oxygen is reduced to water |
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Term
| state the steps of glycolysis |
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Definition
glucose accepts a phosphate from ATP-->ADP, becomes glucose-6-phosphate
isomerizes into fructose-6-phosphate
accepts another phosphate from ATP-->ADP, becomes fructose-1,6-phosphate
splits into TWO molecules of 2-glyceraldehyde-3-phosphate
[this uses up 2ATP]
[from here on in all steps repeated twice, once for each 3-carbon molecule]
NAD+ --> NADH [2NADH total]
2-glyceraldehyde-3-phosphate loses a phosphate twice to make two ADP-->ATP [4ATP total]
and two pyruvates |
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Term
| what happens after glycolysis in an anaerobic environment? |
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Definition
| pyruvate --> lactate, turning NADH --> NAD+ and allowing glycolysis to continue (this is pretty inefficient) |
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Term
| what are two methods of getting acetyl CoA? |
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Definition
1. glucose --> pyruvate and add coenzyme A makes acetyle CoA
2. fatty acid breakdown will make many acetyle CoA molecules |
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Term
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Definition
two membranes; outer one is permeable, inner one is not.
the space between them is called the intermembrane space; the space in the inner one is the matrix.
the inner membrane is folded, or vaginated, forming cristae.
it has proteins embedded in it for controlling oxydation reactions, pumping protons, etc. |
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Term
| what happens between glycolysis and the citric acid cycle? |
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Definition
pyruvate reacts with coenzyme A to make acetyl CoA (2 molecules because two pyruvates)
each of these produce 1 CO2 and 1NADH |
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Term
| describe the citric acid cycle |
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Definition
all the following happens TWICE, once for each molecule of pyruvate.
acetyle CoA (2carbon) combines with oxaloacetate (4carbon) to make CITRATE (6carbon)
- this is isomerized a bunch
then it is turned to a 5carbon, giving off a molecule of CO2 and one of NADH
this happens again and turns it into a 4carbon, giving off another CO2 and NADH
then it is regenerated into a 6carbon! this gives off:
- 1 ATP
- 1 NADH
- 1 FADH2
score thusfar: 3NADH, 1ATP, 1FADH2 repeated twice because there are two molecules of acetyl CoA |
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