Which Is Usually the Slowest Way to Regulate a Reaction

question 65

Multiple Choice

Which is usually the slowest way to regulate a reaction in a metabolic pathway?

• A)Allosteric modulation.
• B)Covalent modification.
• C)Changing the enzyme concentration.
• D)All of the above are usually equally as fast.

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Definitions:

Cortex

In plants, ground tissue bounded by the epidermis and vascular tissue in stems and roots; in animals, outer layer of an organ, such as the cortex of the kidney or adrenal gland.

Vascular Cylinder

The central part of a plant's root system that contains the plant's vascular tissue, including xylem and phloem, for water and nutrient transport.

Casparian Strip

A band of cell wall material in the roots of plants that is impervious to water and solutes, controlling the flow into the vascular system.

Endodermis

The endodermis is the innermost layer of cells in the root cortex of plants, serving as a selective barrier that regulates the flow of water and nutrients from the soil into the vascular system.