front 1 catabolic pathways | back 1 occur when molecules are broken down and their energy is released |
front 2 two important catabolic pathways to know | back 2 fermentation and aerobic respiration |
front 3 fermentation | back 3 the partial degradation of sugars without the use of oxygen |
front 4 aerobic respiration | back 4 the most prevalent and efficient catabolic pathway energy from biological macromolecules is used to produce ATP oxygen is consumed as a reactant term cellular respiration will be used to refer to this |
front 5 in cellular respiration... | back 5 carbohydrates, fats, and proteins can all be broken down to release energy |
front 6 chemical rxn for cellular respiration | back 6 C6H12O6 + 6O2 -> 6 CO2 + 6 H2O + energy |
front 7 exergonic release of energy from glucose... | back 7 is used to phosphorylate ADP to ATP |
front 8 life processes... | back 8 constantly consume ATP |
front 9 cellular respiration burns fuels and... | back 9 uses the energy to regenerate ATP |
front 10 oxidation-reduction (redox) reactions | back 10 electrons and transferred from one reactant to another the reactions of cellular respiration |
front 11 oxidation | back 11 loss of one or more electrons from a reactant loses electrons and loses energy |
front 12 reduction | back 12 the gain of one or more electrons gains electrons and gains energy |
front 13 at key steps in cellular respiration... | back 13 electrons are stripped from glucose electrons and protons travel together, forming hydrogen atoms |
front 14 how are hydrogen atoms transferred to oxygen? | back 14 NAD+ |
front 15 NAD+ | back 15 electron carrier coenzyme derivative of the B vitamin niacin |
front 16 NAD+ accepts... | back 16 two electrons + stabilizing hydrogen ion forms NADH NADH has been reduced, gained energy |
front 17 glycolysis | back 17 glucose is broken down into two pyruvate molecules six-carbon glucose -> two three-carbon sugars -> two three-carbon acids (pyruvate) |
front 18 where does glycolysis occur? | back 18 the cytosol |
front 19 ATP-consuming phase of glycolysis | back 19 two ATP molecules are consumed helps destabilize glucose and make it more reactive |
front 20 ATP-producing phase of glycolysis | back 20 four ATP molecules are produced |
front 21 glycolysis results in a net gain of how many ATP molecules? | back 21 2 |
front 22 products of glycolysis | back 22 2 NADH 2 ATP (net gain) 2 pyruvate - which head to the Krebs Cycle |
front 23 most of the potential energy of glucose molecules resides where, after glycolysis occurs? | back 23 in the remaining two pyruvates |
front 24 what happens after glycolysis? | back 24 pyruvate is oxidized to Acetyl CoA |
front 25 how does pyruvate move from the cytosol into the matrix of the mitochondria? | back 25 via a transport protein |
front 26 what happens in the matrix of the mitochondria when the pyruvate is moved in? | back 26 an enzyme complex catalyzes three reactions 1) CO2 molecule is removed 2) electrons are stripped from pyruvate to convert NAD+ to NADH 3) coenzyme A joins with remaining two-carbon fragment to form acetyl CoA |
front 27 how many acetyl CoA molecules are produced per glucose molecule? | back 27 2 |
front 28 where does the acetyl CoA produced go? | back 28 it enters the citric acid cycle |
front 29 citric acid cycle | back 29 the job of breaking down glucose is completed with CO2 released as a waste product |
front 30 where does the citric acid cycle occur? | back 30 the mitochondrial matrix |
front 31 each turn of the citric acid cycle requires the input of how many acetyl CoA? | back 31 1 |
front 32 how many turns must the citric acid cycle make before glucose is completely oxidized? | back 32 2 |
front 33 each turn of the citric acid cycle produces... | back 33 2 CO2 3 NADH 1 FADH2 1 ATP |
front 34 the total products of the citric acid cycle are... (needs two turns to fully oxidize glucose) | back 34 4 CO2 6 NADH 2 FADH2 2 ATP |
front 35 at the end of the citric acid cycle... | back 35 the six original carbons in glucose have been released as CO2 |
front 36 why have only 2 ATP molecules been produced at the end of the citric acid cycle when all of the 6 original carbons have been released as CO2? | back 36 the energy is held in the electrons in the electron carriers, NADH and FADH2 |
front 37 where is the electron transport chain located? | back 37 it is embedded in the inner membrane of the mitochondria |
front 38 what is the electron transport chain composed of? | back 38 three transmembrane proteins - work as hydrogen pumps two carrier molecules - transport electrons between hydrogen pumps *thousands of these are present in the inner mitochondrial membrane |
front 39 what is the electron transport chain powered by? | back 39 electrons from electron carrier molecules NADH and FADH2 |
front 40 how does the electron transport chain work? | back 40 as the electrons flow through the electron chain, the loss of energy by electrons is used to power the pumping of protons across the inner membrane |
front 41 what happens at the end of the electron chain? | back 41 the electrons combine with two hydrogen ions and oxygen to form water |
front 42 what is the final electron acceptor? | back 42 O2 |
front 43 what happens if oxygen isn't available at the end of the electron transport chain? | back 43 the transport of electrons comes to a screeching halt no hydrogen ions are pumped, no ATP is produced |
front 44 how do hydrogen ions flow back down their gradient? | back 44 ATP synthase |
front 45 what is ATP synthase? | back 45 a channel in the transmembrane protein harnesses the electrochemical gradient to to phosphorylate ADP, forming ATP |
front 46 what is an electrochemical gradient? | back 46 gradient of hydrogen ions stores potential energy by a diffusion gradient and an electric charge gradient across a membrane |
front 47 where are electrochemical gradients found in cellular respiration? | back 47 across the inner membrane of mitochondria |
front 48 where are electrochemical gradients found in photosynthesis? | back 48 across the inner membrane of chloroplasts |
front 49 chemiosmosis | back 49 an energy-coupling mechanism uses stored energy in the form of an H+ gradient across a membrane to drive cellular work ie. ATP synthesis |
front 50 the electron transport chain and chemiosmosis together result in... | back 50 oxidative phosphorylation |
front 51 why is the term oxidative phosphorylation used to describe electron transport chain and chemiosmosis? | back 51 ADP is phosphorylated oxygen is necessary to keep the electrons flowing |
front 52 fermentation | back 52 an expansion of glycolysis ATP is generated without oxygen |
front 53 fermentation consists of... | back 53 glycolysis reactions that regenerate NAD+ |
front 54 what molecule accepts electrons in glycolysis? | back 54 NAD+ oxygen is not needed to accept electrons |
front 55 alcohol fermentation | back 55 pyruvate is converted into ethanol CO2 is released -> NADH oxidized in the process creates more NAD+ |
front 56 lactic acid fermentation | back 56 pyruvate is reduced by NADH NAD+ formed in the process lactate produced as a waste product |
front 57 what else can be used to generate ATP during cellular respiration other than glucose and other sugars? | back 57 proteins and fats |
front 58 phosphofructokinase (PFK) | back 58 allosteric enzyme functions in early pathway of glycolysis acts as a regulator of respiration |
front 59 with adequate ATP... | back 59 the breakdown of glucose to pyruvate is not required |
front 60 when ATP is needed in higher concentrations... | back 60 a product of ADP acts as an allosteric regulator on PFK increases ATP production |
front 61 PFK is considered... | back 61 the pacemaker of respiration controls the rate of the entire process of cellular respiration |
front 62 PFK is a great example of... | back 62 the regulation of an enzymatic process by negative feedback |