Chemoautotrophic Bacteria Called _______ Carry Out a Two-Step Process

question 57

Multiple Choice

Chemoautotrophic bacteria called _______ carry out a two-step process.Two genera, Nitrosomonas and Nitrosococcus, convert _______, and then Nitrobacter converts _______, which is most usable by plants.

• A) nitrogen fixers; ammonia (NH₃) to nitrite ions (NO₂^-); nitrite to nitrate (NO₃^-)
• B) denitrifiers; ammonia (NH₃) to nitrite ions (NO₂^-); nitrite to nitrate (NO₃^-)
• C) denitrifiers; nitrite to nitrate (NO₃^-); ammonia (NH₃) to nitrite ions (NO₂^-)
• D) nitrifiers; nitrite to nitrate (NO₃^-); ammonia (NH₃) to nitrite ions (NO₂^-)
• E) nitrifiers; ammonia (NH₃) to nitrite ions (NO₂^-); nitrite to nitrate (NO₃^-)

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Definitions:

Variable Cost

Financial obligations that shift depending on production or sales levels, notably materials and workforce expenses.

Fixed Cost

Costs that do not vary with the level of production or sales.

Period Cost

Expenses not directly tied to production activity, such as administrative and selling expenses, that are expensed in the accounting period in which they are incurred.

Contribution Margin Ratio

A metric that shows the percentage of sales revenue left after variable costs are deducted, indicating how much contributes to fixed costs and profits.