From Studying Ecosystems and Biomes,it May Seem as If There

question 80

Essay

From studying ecosystems and biomes,it may seem as if there is complete "bottom up" control,that the producers determine the life and success of the ecosystem.Yet closer examination shows "top down" control by the third trophic level is essential as well.Evaluate why this is so,citing at least one good example.

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Definitions:

Break-even Sales

Break-even sales is the amount of revenue required to cover both fixed and variable costs, resulting in no profit or loss.

Variable Costs

Costs that fluctuate in direct relation to production levels or sales figures.

Fixed Costs

Costs that do not vary with the level of production or sales, remaining constant regardless of business activity.

Sales Revenue

The total amount earned from the sale of goods or services before any costs or expenses are deducted.