In cellular respiration, glucose gives up ATP, by using ______. The waste products will be ____ & _____
Every other molecule we eat is converted into _______ or other molecules that will go through a similar _____ pathway.
The metabolic pathway for food stuff ingested will always be _______ reaction
The complete combustion of glucose yields _____ kcal/mol which is a lot of energy and must be released _______.
- -686 kcal/mol
The energy that allows you to make ATP is derived from the combustion of _____. ATP is then used ______ to power the cell. We breakdown food ______ and use the products to form ATP ______
The metabolic pathway that leads to either cellular respiration or fermentation: (3,2,3)
- Photosynthesis mass produces glucose with CO2 (endergonic)
- The glucose is then broken from a 6-carbon molecule into two 3-carbon molecules. This is called glycolysis and it is exergonic
- The resulting molecule from glycolysis is pyruvate (exergonic)
- If O2 is present (aerobic):
- A)We will use the energy from that to produce about 32 ATP
- B)Waste product H2O & CO2
If O2 is not present (anaerobic):
- A)Anaerobic fermentation
- B)Net result is 2 ATP
- C)Yeast can survive off of this style (small amounts of oxygen unlike us)
If a molecule gains an electron, it has been ______. If a molecule has lost an electron, it has been ______. ______ is the loss of one or more electrons. The reducing agent is _______ and the oxidizing agent is _______.
ATP is produced from the _______ of glucose. _____ is usually the greatest reducing agent
- oxidation (stealing its electrons)
Cellular respiration begins with ______ that occurs in the _______/_______
What type of fermentation do humans undergo
Lactic acid fermentation
What is inside the mitochondrial matrix?
Electron transport chain occurs along the ______ in the mitochondria
cristae aka inner membrane
Glycolysis/pyruvate oxidation/citric acid cycle broad strokes story: (9)
- Glycolysis is just 10 enzymatic reactions
- Starts with a substrate which is glucose, hexokinase is the first enzyme and we get a product, which happens to be the substrate for the next enzyme
- That enzyme (*phosphohexose isomerase) will modify the substrate and pass it along to enzyme #3 (phosophofructokinase)
- The product of the reaction with #3 will be the substrate for enzyme #4 (aldolase)
- This continues on and the end result is pyruvate.
- Pyruvate will make its way into the matrix where "pyruvate oxidation" will occur aka losing its electrons
- As a result, the citric acid cycle is based around the loss of all electrons
- Lost electrons will be used to do work in the electron transport chain along the cristae
- End result of all this is to make ATP
The purpose of glycolysis is to make ______ because its the only thing that can get inside the ______ _____
- mitochondrial matrix
Glycolysis has a net product of ___ ATPs, ___ pyruvates, & ___ NADHs. It also generates ____ CO2. For instance if we started with 6 glucose carbon molecules, ____ carbon molecules will enter the mitochondria. No ______ occurs
- 2 pyruvates, 2 ATP, 2 NADH
- no CO2
- 6 carbon molecules
The most valuable product of glycolysis is _____ because of all the ____ it can yield to produce ATP. The second most valuable is _____ which will give us _____ electrons that can give us more ATP
Kreb cycle aka
citric acid cycle
Which is more valuable NADH produced in the matrix or oustide? Why?
Inside the matrix, because it costs energy to transport it into the matrix
Phosphorylation means from ATP to substrate, while substrate-level phosphorylation means from, for instance a glucose derivative to _____ to make ____
ADP to make ATP
Glycolysis (feature length story):
just call the products glucose derivatives
*= not tested
- Hexokinase is bigger than glucose, and would have glucose at its active site as well as ATP for phosphorylation.
- The reaction that would be catalyzed would be the transfer of a phosphate onto the glucose
- The product would be (*glucose 6-phosphate) G6P which will be the substrate for next enzyme (*phosphohexose isomerase)
- The importance of this reaction is that it produces F6P (*fructose 6-phosphate), the only thing that can bind to the next enzyme phosphofructokinase
- Keep in mind: at the active site of phosphofructokinase there will be F6P and ATP (in order to phosphorylate F6P and create FBP)
- The enzyme for the substrate FBP (fructose 1,6 biphosphate or just glucose derivative) will be aldolase
- Aldolase will break FBP into two products, we still have our 6 carbons they're just in two 3-carbon molecules.
- The products will be *dihydroxyacetone phosphate (DAP) & glyceraldehyde 3-phosphate aka G3P (most important)
- DAP is converted into G3P anyway by an enzyme (*some isomerase)
- Most important point is aldolase leads to two 3 carbon molecules that are very electron rich, (there have been no redox reactions of any kind)
- The next enzyme (will be *triose phosphate dehydrogenase) which will catalyzes a (the 1st) redox reaction and catalyzed insertion of an inorganic phosphate (not considered conventional phosphorylation)
- Inorganic phosphate will bind to the active cite and the enzyme will place it on the molecule
- The result: since there are 2 G3Ps, each will get a phosphate and will lose 2 electrons
- The 4 electrons lost will be transferred to NADH
- The product will be BPG (glucose derivative) the substrate for the next enzyme *phosphoglycerate kinase
- Phosphoglycerate kinase will catalyze substrate-level phosphorylation on two 3-carbon molecules that will result in our next glucose derivatives *two 3PGs
- The process repeats for 2 more low profile enzymes: *phosphoglyceromutase & *enolase.
- Point is the eventual product will be pyruvate kinase and the product of this will be the star of the show: pyruvate & 2nd ATP. This will be done via substrate-level phosphorylation
- At this point we've made 4 ATPs, and lost 2 ATPs
- We still need to get rid of A LOT of energy so we will have to oxidize pyruvate
Pyruvate oxidation implies? Pyruvate oxidation can be seen as _______ which will be the production of ____ and removal of ____
- stealing electrons from pyruvate
Pyruvate oxidation story (4):
- Active transport is used to transport the 2 pyruvates &NADHs produced during glycolysis into the mitochondrial matrix
- There we will come across a really large enzyme complex (pyruvate dehydrogenase) that will turn 3-carbon pyruvate (the substrate) into 2-carbon acetate, burning our 1st carbon
- At the same time, pyruvate dehydrogenase will add coenzyme A to acetate yielding acetyl CoA (important because that’s the only way it'll react with the next enzyme)
Free energy summary before pyruvate oxidation: Will have gotten ____ energy from glucose as possible. We won't have made any ___, but the energy will be held up in _____ _____. All the electrons will move from ______ molecules to _____ _____ and a couple of ____ will have been made along the way.
- electron carriers
- glucose molecules
- electron carriers
Glycolysis is an _______ reaction because we put ______ _____ into the reaction
The generated ATP in glycolysis is used by the cell and the pyruvate and NADH is moved to the _______ _____
Pruvate oxidation summary: (3)
- 2 decarboxylation events (1 per molecule)
- 2 coenzyme As added
- 2 NADHs yielded
For the citric acid cycle the only enzyme names that are need to know are _______ which is the beginning product & ______ which is the end product.
Oxaloacetate will be the most ______ and citrate will be the highly _______.
______ is added to oxaloacetate to make citrate and it is very _____ ____ although they are eventually removed.
What we need for the citric acid cycle (6):
- Acetyl CoA (electron source)
- Electron carriers:Water, FAD & NAD+
Purpose of the citric acid cycle is to move electrons from _____ ____ to which 2 destinations?
- Acetyl CoA
- FAD to make FADH2
- NAD+ to make NADH
The most important product of pyruvate oxidation is ______ ___
Citric acid story
- 1st) In the first reaction we will add Acetyl CoA (2carbons) to oxaloacetate (4carbons) to get citrate (6carbon molecules) this will cost our coenzyme A
- 2nd) From isocitrate to a-ketogluterate there is a redox reaction (NAD+-NADH) and there is a decarboxylation
- 3rd) From a-ketogluterate to succinyl CoA there is a redox reaction, a decarboxylation and an addition of Acetyl CoA. We've also lost all 3 of the carbons by this point remember one is lost in pyruvate oxidation. There are however, some electrons to pick up
- 4th) From succinyl CoA to succinate we will catalyze a reaction that produces GTP and transfer that a phosphate to that GTP to make 2 ATPs
- 5th) From succinate to fumarate there is a redox reaction
- 6th) From fumurate to malate there is a redox reaction
- 7th) from malate to oxaloacetate there is a redox reaction
From a-ketogluterate to succinyl CoA there is a redox reaction, a decarboxylation and an addition of Acetyl CoA. This is basically _____ ______
Citric acid cycle summary products:
6NADH, 2FADH, 2ATP, 4CO2 burned
Citric acid cycle occurs in the _____ _____
Story about ATP binding at active and regulatory site during glycolysis:
- All enzymes are expected to have two sites, Active sites and regulatory sites
- Phosphofructokinase will phosphorylate aka transfer a phosphate from ATP to the glucose derivative
- The products: ADP & a phosphorylated glucose derivative
- ATP will also bind to the regulatory site of the enzyme (fructose 6 -phosphate)
- This is a noncompetitive inhibition (not bound to the active site) so what will happen?
- Result is a conformational change that halts the reaction
- If ATP is bound to the regulatory site, there will be no phosphorylation (homeostatic mechanism)
- Keep in mind the regulatory site has a very high affinity for ATP. Even if the concentration of ATP is low, it can still bind, however, is more likely to bind to the active site
- Either way, this binding will stop phosphorylation of the glucose derivative. ATP will not be allowed to transfer its phosphate.
- This will stop: glycolysis, citric acid cycle, electric transport chain, ATP production
- If you reduced the regulatory site's affinity for ATP, what would have to happen for ATP to still bind? ATP concentration would have to increase
- The point of cellular respiration is to make more ATP. When we have made a lot, ATP will bind to the regulatory site on the enzyme which will lead to a halting of the reaction that is producing ATP.