Phosphofructokinase Is Regulated by a Number of Factors,including High Levels

question 19

Multiple Choice

Phosphofructokinase is regulated by a number of factors,including high levels of ATP.Why is this enzyme regulated by ATP levels?

• A)If ATP levels are high,this provides a mechanism to directly inhibit the Citric acid cycle,thus preventing further generation of NADH,FADH₂ and ATP molecules that are not needed.
• B)If ATP levels are high,it is important to directly inhibit the reaction that commits the substrate to glycolysis to allow the substrate to be available for other reactions,since the cell has ample energy.
• C)If ATP levels are high,it is important to inhibit ATP synthase,and phosphofructokinase directly inhibits ATP synthase.
• D)If ATP levels are high,this provides a mechanism to directly inhibit the electron transport chain,thus preventing the formation of a proton gradient in the intermembrane space of mitochondria.

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Definitions:

Carbon Dioxide

This is a gas that cannot be seen or smelled, emerging from the combustion of carbon and various organic substances, along with being a part of the respiration process. Naturally occurring in our atmosphere, it is critical for the photosynthesis process in plants.

Large City

A highly populated urban area with a significant economic, political, and cultural influence both regionally and nationally.

Acid Deposition

A broad term that includes any form of precipitation with acidic components, such as sulfuric or nitric acid, falling to the ground.

Highest Levels

The most extreme or advanced point within a specific context or system.