In Step 2 of the Citric Acid Cycle, the Enzyme

question 49

Multiple Choice

In step 2 of the citric acid cycle, the enzyme aconitase generates isocitrate from citrate.Which of the following statements about this reaction is TRUE?

• A)There is a substantial free-energy difference between the reactants and products of this reaction.
• B)The unbonded electrons from hydroxide ions provide energy for this reaction.
• C)The aconitase enzyme functions as a mutase in this reaction.
• D)The reaction sequence first generates one molecule of water and then consumes one molecule of water.

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Definitions:

Cell Membrane

The semipermeable membrane surrounding the cytoplasm of a cell, controlling entry and exit of substances.

Cytoplasm

The jelly-like substance within a cell, excluding the nucleus, that contains organelles, cytosol, and is the site of numerous biochemical reactions.

Nucleus

The central and most important part of an object, movement, or group, forming the basis for its activity and growth, or in cells, a membrane-bound organelle that contains the cell's chromosomes.

Cell Membrane

The semipermeable membrane surrounding the cytoplasm of a cell, responsible for controlling the passage of substances in and out of the cell.