When Certain Molecules Are Pumped Across Biological Membranes Against a Concentration

question 22

Multiple Choice

When certain molecules are pumped across biological membranes against a concentration gradient via active transport, ATP is used. In our body cells, for example, sugars are actively transported and metabolized within the membrane-enclosed mitochondria. Prokaryotes, in contrast, lack mitochondria but are nonetheless able to metabolize the same sugars. Based on the details provided in this scenario, which of the following statements is expected to be TRUE?

• A)The sugar-digesting enzymes in eukaryotic cells, such as sucrase, are not the same sugar-digesting enzymes found in prokaryotic cells.
• B)Overall, prokaryotes will gain more ATP per sugar molecule metabolized than will eukaryotes.
• C)Prokaryotes and eukaryotes should have the same metabolic efficiency when digesting the same sugars, assuming their enzymes are the same.
• D)Sugar metabolism in prokaryotes is exergonic, whereas in eukaryotes it is endergonic.

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Definitions:

Accumulated Depreciation

The total amount of depreciation expense that has been recorded against a fixed asset over its useful life to date.

Original Cost

The initial price paid to acquire an asset before any depreciation or amortization.

Net Income

The earnings a company retains following the deduction of all costs and taxes from its overall income.

Accumulated Depreciation

The total amount of depreciation expense that has been recorded for an asset since it was put into use, subtracted from its original cost on the balance sheet.