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Where is ATP produced?

The inner membrane of the mitochondria


how many carbons does compound X have?



ATP: Where in the mitochondria does this reaction take place?

the electron transport chain produces ATP


Could this reaction drive the synthesis of ATP from ADP?



How does the cell modify its energy production? ( In other words, how does the cell sense the amount of ATP and make adjustments)



Draw a diagram of the mitochondria showing how ATP is generated by chemiosmotic synthesis.



Discuss how the electron transport chain is a good example of a structure/function relationship.



Give an example of a chemical rearrangement in glycolysis or the citric acid cycle. What is the purpose of these Chemical rearrangements?



Give an example of an oxidation/reduction step in the citric acid cycle. Which molecule is reduced/ which is oxidized?



what is the function of enzymes----how do they work?

-Function: by catalyzing covalent bond breakage or formation
-They bind to one or more ligands (called substrates), && convert them into chemically modifies products, over & over again with rapidity.
*This results in an elaborate network of METABOLIC PATHWAYS that provides the cell with energy and generates the many large and small molecules that cells need.


How do enzymes lower the activation energy?

-When atoms of substrates assume altered geometry and electron distribution


Enzyme Regulation: Competitive inhibition and noncompetitive inhibition



ENZYME REGULATION: Feedback (can be competitive or allosteric)



ENZYME REGULATION: Allosteric (inhibition or activation)

These Enzymes, have 2 or more binding sites that influence each other. and can adopt 2 or more slightly different conformations
-The regulartory molecule often has a shape that is totally different from the shape of the enzymes's preferred substrate .
-This made researchers realize that many enzymes must have @ least 2 diff. binding sites on their surface: Active site recognizing substrates & 1 or more sites that recognize regulatory molecules. Which communicate allowing catalytic evens at the active site to be influenced by the binding of the regulatory molecule at its separate site.


ENZYME REGULATION: Covalent modification -
e.g. phosphorylation/dephosphorylation

-[These also control the location & interaction of proteins]
-Phosphorylation can control activity by causing a conformation change
-The removal of the phosphate group is called DEPHOSPHORYLATION & is catalyzed by a protein phosphatase.

**I molecule of ATP hydrolyzed w/ each turn of cycle


Where in the cell does NADH, ATP, & pyruvate take place and, what is generated?



Which steps generate ATP and NADH in glycolysis?

ATP is generated at 6,7, and 10
NADH is generated in step 6


How is enzyme regulation of glycolysis possible?

The enzymes responsible for catalyzing are the primary steps for allosteric enzyme regulation. Generally, enzymes that catalyze essentially irreversible steps in metabolic pathways are potential sites for regulatory control


In the Citric Acid Cycle, Where is ATP produced by substrate level phosphorylation?

Four ATP are produced by substrate-level phosphorylation. Recall that substrate-level phosphorylation is the production of ATP using energy from other high-energy compounds but without the use of the electron transport system in the mitochondria.


Citric Acid Cycle: Where is NADH and FADH2 generated?

Happens within the Mitochondria.
Electrons are carried to the electron transport chain by the molecules NADH and FADH2, which are produced in many cellular processes, included glycolysis and citric acid cycle


Citric Acid Cycle: Where is CO2 generated?

During steps 5 and 6 of the citric acid cycle


Citric Acid Cycle: Whats the relationship between NADH production and oxidation/reduction?

The NADH and succinate generated in the citric acid cycle are oxidized, releasing energy to power the ATP synthase.


How can the Citric Acid Cycle be turned UP or DOWN?



Which complexes pump H+ across the membrane?

In eukaryotic cells, the electron carriers are spatially arranged in the inner mitochondrial membrane in such a way that H+ is accepted from the mitochondrial matrix and deposited in the intermembrane space.


What is an Fe/S center?

iron-sulfur protein (Fe*S), one of a family of proteins with both iron and sulfur tightly bound. The center of a NADH Dehydrogenase Complex.

Iron-sulfur centers transfer only one electron even if they contain two or more iron atoms, because of the close proximity of the iron atoms.


Whats the mechanism for pumping H+?

certain members of the electron transport chain accept and release protons (H+) along with electrons. The aqueous solutions inside and surrounding the cell are a ready source of H+. At certain steps along the chain, electron transfers cause H+ to be taken up and released into the surrounding solution.

In eukaryotic cells, the electron carriers are spatially arranged in the inner mitochondrial membrane in such a way that H+ is accepted from the mitochondrial matrix and deposited in the intermembrane space.


How is ATP Synthase situated in the membranes? What does it do?

In mitochondria ATP synthase is located in the inner membrane, the hydrophilic portion is sticking into matrix.

ATP synthase uses ATP to generate protonmotive force necessary for ion transport and flagella motility.


General Structure of a cytoChrome?



How is ATP generated by chemiosmotic synthesis?

ATP synthesis is coupled to electron transport. Some of the energy released as electrons pass along the electron transport chain is used to pump protons (hydrogen ions) across the inner mitochondrial membrane from the matrix into the intermembrane space

This process, in which energy stored in the form of a hydrogen ion gradient across a membrane is used to drive cellular work such as the synthesis of ATP, is called chemiosmosis.


How is NADH regenerated (under anaeorbic conditions)

-Alcohol fermentation
-Lactic Acid