What Do Phototropin and ABA Have in Common

question 20

Multiple Choice

What do phototropin and ABA have in common?

• A)They induce stomata closing.
• B)They regulate opening and closing of water pores in the plasma membrane.
• C)They regulate activity of H⁺-ATPases.
• D)They are localized in the plasma membrane.
• E)All of the above apply.

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Definitions:

Step-Variable Costs

Costs that remain fixed for certain levels of production or capacity but can change in steps when a critical level is surpassed.

Fixed Costs

Expenses that remain constant for a given period of time regardless of the level of outputs or activity.

Step-Fixed Costs

Costs that remain constant for a certain level of activity but jump to a higher level when activity increases beyond that threshold.

Production Line

A production line is an arrangement of machines and workers in a factory where a succession of operations is performed on a product to complete its manufacture.