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Side ASide B
When do redox reactions release energy?
When electrons move closer to electronegative atoms.
What does respiration generally involve?
Glycolysis Krebs cycle Electron transport
What does the Krebs cycle complete?
The energy-yielding oxidation of organic molecules.
What does the inner mitochondrial membrane do?
Couples electron transport to ATP synthesis.
What generates many ATP molecules for each sugar molecule it oxidizes?
What helps a cell systematically degrade complex organic molecules that are rich in potential energy to simpler waste products with less energy
Metabolic pathways that release stored energy by breaking down complex molecules are called..?
Which catabolic process is a partial degradation of sugars that occurs without the help of oxygen?
Which catabolic pathway is most prevalent and efficient, and in which oxygen is consumed as a reactant along with the organic fuel?
In eukaryotic cells, what houses most of the equipment for cellular repiration?
What is the word equation for the overall process of Cellular Respiration?
Organic Compounds + Oxygen --> Carbon dioxide +Water+Energy
Into what does the C6H12O6 degrade ?
6CO2 6H20 and Energy (ATP+Heat)
What chemical drive shaft (the pivotal molecule in cellular energetics) links catabolism to work?
What does ATP stand for?
When a cell taps triphosphate tail of ATP by using enzymes to transfer phosphate groups from ATP to other compounds...?
Phosphorylation- primes a molecule to undergo some kind of change that performs work, and the molecule loses its phosphate group in the process.
What is the "price" of most cellular work?
The conversion of ATP to ADP and inorganic molecules.
What must a cell do to continue working?
Recycle ATP/ Regenerate ATP from ADP and inorganic molecules
Reactions that result in the transfer of one or more (e-) from one reactant to another are called ?
Abrev. for Oxidation-reduction reactions
The loss of electrons is called...?
In a redox reaction what agent is the electron donor and electron acceptor?
Electron donor is the REDUCING AGENT Electron acceptor is the OXIDIZNG AGENT
The addition of electrons is called...?
Glucose is oxidized, oxygen is reduced, and what happends to the potential energy of the electrons?
Electrons loose potential energy.
Why does the rich reservoir of electrons in a cell not spontaneously combine with O2?
They lack the activation energy.
What lowers the barrier of activation energy, allowing fuels to be oxidized slowly?
Does cellular respiration oxidize glucose in a single step? Explain.
No. Glucose and other fuels are broken down gradually in a series of steps, each catalyzed by a specific enzyme
Dehydrogenase enzymes do what?
Strip two hydrogen atoms from the fuel (e.g., glucose), pass two electrons and one proton to NAD+ and release H+.
When is energy is tapped to synthesize ATP?
As electrons “fall” from NADH to oxygen.
Cellular respiration uses an electron transport chain to..?
Break the fall of electrons to O2 into several steps.
Respiration occurs in three metabolic stages:
1) Glycolysis 2) Krebs cycle 3) e-transport chain and oxidative phosphorylation
What occurs in the cytosol, begins the degradation by breaking glucose into two molecules of compound called pyruvate?
Which takes place within the mitochondrial matrix, completes the job by composing a deribative of pyruvate to carbon dioxide?
Are some of the steps of glycolysis and the Krebs cycle redox reactions from NAD+ to NADH?
The energy released at each step of the chain is sotred in a form the mitochondrion can use to make ATP. This mode of ATP synthesis is called?
Oxidtaive phosphorylation accounts for what percent of ATP generated by repiration?
What is substrate-level phosphorylation?
Mode of ATP synthess that occurs when an enzye transfers a phosphate group from a substrate molecule to ADP.
How does glycolysis harvest chemical energy?
It begins catabolism by breaking glucose into two molecules of pyruvate.
Glycolysis occurs in the...?
The Krebs cycle occurs in the..?
The Krebs cycle degrades pyruvate to...?
What does ATP synthase do?
This enzyme actually makes ATP from ADP and inorganic phosphate.
During glycolysis, glucose, a six carbon-sugar, is split into..?
Two, three-carbon sugars
Each of the ten steps in glycolysis is catalyzed by a specific..?
Glycolysis can be divided into two phases..?
an energy investment phase and an energy payoff phase.
The net yield from glycolysis is... ?
2 ATP and 2 NADH per glucose.
CO2 is not produced in glycolysis?
Glycolysis occurs whether O2 is present or not?
The Krebs cycle is named after __________ who was largely responsible for elucidating its pathways in the ____
Hans Krebs 1930's
The conversion of pyruvate and the Krebs cycle produces large quantities of ...?
What is the cristae?
The inner membrane of the mitochondrion.
Does The electron transport chain generates ATP directly?
What is the function of the Electron Transport chain in Respiration?
Break the large free energy drop from food to oxygen into a series of smaller steps that release energy in manageable amounts.
How much ATP is generated in each of the Metabolic stages of Respiration
Glycolysis 2 ATP Krebs Cycle 2 ATP Electron Transport chain and Oxidative Phosphorylation 34 ATP
Fermenation enables some cells to produce ATP without the help of...?
Anaerobic catabolism of organic nutrients can occur by what?
In _____ fermentation, pyruvate is converted to ethanol in two steps?
During __________ fermentation, pyruvate is directly reduced by NADH to form lactate as a waste product.
Human muscle cells make ATP by lactic acid fermentation when...?
Oxygen is scarce.
Is Cellular respiration remarkably efficient in energy conversion?
Electrons "fall" from organic molecules to oxygen during...?