Glycolysis
Breakdown of sugar (glucose is a 6 carbon sugar)
Produces 2 pyruvates (3 carbon sugars)
Takes place in cytoplasm
2 ATP lost but 4 produced (net of 2 ATP)
2 NADH produced
aerobic respiration
cellular respiration that uses oxygen
anaerobic respiration
Process in which prokaryotes use substances other than oxygen as reactants in the process that harvest chemical energy without oxygen
NADH
Formed by dehydrogenase
Electron Carrier
Used in the electron transport chain to produce more ATP
Link reaction
2 pyruvate in and out is 2 CO2 and 2 Acetyl attached to coenzyme A (coA)
Citric Acid Cycle (Krebs Cycle)
Takes place in the matrix of mitochondria
2 carbon molecule (Acetyl CoA) and 4 carbon molecule (oxaloacetate) combine to produce 6 carbon molecule (Citrate)
6 carbon molecule goes through changes and produced the original 4 carbon molecule at the end
Prod
FADH2
electron carrier produced during the Krebs cycle
Used in the electron transport chain to produce more ATP
Acetyl CoA
Made from pyruvate that is oxidized (a two carbon fragment of pyruvate attached to a coenzyme)
Electron Transport Chain
A series of protein complexes embedded in the mitochondrial membrane where the electrons and protons released by oxidized NADH and FADH2 (go back to NAD+ and FAD) are transferred through, moving down in energy levels, energy is released allowing hydrogen
oxidative phosphorylation
Hydrogen ions (protons) move down their concentration gradients and enter the ATP synthase resulting in the rotation of the ATP synthase (due to proton motive force) which synthesizes ATP from ADP and Pi
Outputs are CO2 and H2O as well as 34 ATP
ATP synthase
The enzyme that make ATP from ADP and inorganic phosphate as protons move through it
Oxidation Reduction Reaction (redox reaction)
Reactions involving electron transfers
Oxidized
Loses electrons
Reduced
Gains electrons
Reducing agent
The electron donor in a redox reaction
Oxidizing agent
The electron acceptor in a redox reaction
Four substages of cellular respiration
Glycolysis
Prep Cycle and Citric Acid Cycle
Electron Transport Chain
Oxidative phosphorylation
Fermentation
A partial degradation of sugars or other organic fuel that occurs without the use of oxygen
Makes it possible for ATP to be continually produced in the absence of oxygen
Involves glycolysis followed by the reduction of pyruvate by NADH
Produces a yield of
How much ATP is produced from one glucose molecule? (How much is invested? How much is made? What is the total yield?) during which stages?
38
2 are invested in glycolysis with 4 produced (net of 2)
2 are produced in the Citric Acid Cycle
34 are produced through oxidative phosphorylation
NAD+
A coenzyme that cycles easily between oxidized and reduced state, thus acting as an electron carrier
Reusable
FAD
an electron carrier that is changed to FADH2, similar to NAD+
Reusable
Why does the oxidation of FADH2 yield less ATP than NADH
because it enters the electron transport chain at a later stage
Glycolysis occurs in the ______ and starts with ______ and produces ______ and ______
cytoplasm
Glucose
2 pyruvate
2 net ATP (4 but needed 2 to start)
Link reaction occurs in the ______ and starts with ______ and produces ______ and ______
Matrix of the mitochondria
2 pyruvate
2 CO2
Acetyl-CoA (Acetyl linked to coenzyme A)
The citric acid cycle occurs in the ______ and starts with ______ and ______ and produces ______ with outputs including ______ and ______
Matrix of the mitochondria
Acetyl
Oxaloacetate
Oxaloacetate
2 ATP
2CO2
The Electron Transport Chain occurs in the ______ and starts with ______ and ______ and produces ______ where the ______ are moved through and release ______allowing ______ to be moved through the protein channels against their concentration gradient. At
Cristae of the mitochondria
NADH
FADH2
Lots of H+
Electrons
Energy
Protons
oxidative phosphorylation # of ATP
34
substrate level phosphorylation vs oxidative phosphorylation
Substrate-level phosphorylation is directly phosphorylating ADP with a phosphate and energy provided from a coupled reaction while Oxidative phosphorylation is when ATP is generated from the oxidation of NADH and FADH2 and the subsequent transfer of elect
oxidative phosphorylation is used in
ATP Synthesis
substrate level phosphorylation is used in
Glycolysis and the Citric Acid Cycle
How is oxaloacetate important in this cycle?
oxaloacetate is joined with acetyl-CoA to form citric acid and is formed at the end of the cycle (which is what makes it a cycle)
What happens when electrons are moved close to an electronegative atom? How is this useful in Cellular Respiration? Why is oxygen of particular interest in this process?
When electrons are moved close to an electronegative atom energy is released, this is useful in cellular respiration because the energy released is used to push H+ against their concentration gradient. The electrons after going through the electron transp
catabolic pathways
Metabolic pathways that release stored energy by breaking down complex molecules into simpler compounds
cellular respiration
The catabolic pathways of aerobic and anaerobic respiration which break down organic molecules and use an electron transport chain for the production of ATP
Chemiosmosis
When H + flows down gradient through the ATP synthase complex, energy is released and used to form ATP
Why is NAD+ called a coenzyme of oxidation-reduction
It becomes a reduced when it accepts electrons from a substrate and becomes oxidized when it passes electrons on to another carrier
The molecule glucose is ______ while oxygen is ______. Cellular respiration is an ______ reaction
Oxidized
Reduced
Exergonic
Why is NAD+ called a coenzyme of oxidation-reduction
It becomes reduced when it accepts electrons from a substrate and becomes oxidized when it passes electrons on to another carrier
What type of phosphorylation occurs during glycolysis
Substrate-level phosphorylation
What coenzyme carries out oxidation of substrates during glycolysis
NAD+
What is the output of glycolysis per glucose molecule
2NADH, 2 pyruvate, and 2 net ATP
A two-carbon molecule acetyl group enters the citric acid cycle. What carbon molecules derived from the acetyl group leave the citric acid cycle?
CO2
What coenzymes carry out oxidation of substrates in the citric acid cycle?
NAD+
What are the outputs of the citric acid cycle
6 NADH, 2 ATP, 2 FADH & 4 CO2
What coenzymes bring hydrogen atoms to the electron transport chain
NADH and FADH2
In the electron transport chain the electrons are ______ and the hydrogen ions are ______
Moved down the electron transport chain
Pumped out into the intermembrane space
Each pair of electrons carried by NADH from the citric acid cycle that passes down the electron transport chain accounts for the build up of how many ATPs?
3
During glycolysis, when each molecule of glucose is catabolized to two molecules of pyruvate, most of the potential energy contained in glucose is where?
Retained in the two pyruvates
The free energy for the oxidation of glucose to CO2 and water is -686 kcal/mol and the free energy for the reduction of NAD+ to NADH is +53 kcal/mol. Why are only two molecules of NADH formed during glycolysis when it appears that as many as a dozen could
Most of the free energy available from the oxidation of glucose remains in pyruvate, one of the products of glycolysis
In the citric acid cycle, pyruvate is oxidized to ______
CO2
In the citric acid cycle...
The last reaction in the citric acid cycle produces a product that is a substrate for the first reaction of the citric acid cycle
The chemiosmotic synthesis of ATP requires what
That the electron transport in the inner mitochondrial membrane be coupled to proton transport across the membrane
The redox reactions of the electron transport chain
Are directly coupled to the movement of protons across a membrane
How do cellular respiration and breathing differ
Cellular respiration and breathing differ in that cellular respiration is at the cellular level, whereas breathing is at the organismal level