Biochem: Enzyme Regulation Part I

Enzymes that effect the overall rate of a series of metabolic reactions

• regulatory enzymes

• proenzyme

• coenzyme

• allosteric site

Rates of enzyme-catalyzed reactions in the body are controlled by these principles: When more of a particular substance is needed, reaction rates _________; When a substance is not needed anymore, reaction rate _______.

• stay the same;increase

• Increase;decrease

• decrease;increase

• decrease; stay the same

The ability to control the rate of the overall metabolic pathway allows the cell to _____.

• use up all of its enzymes

• keep a set amount of enzymes at all times

• adapt to its changing needs

• maintain the same amounts of enzymes

Catalyze the rate-limiting or slowest step in a pathway.

• coenzyme

• Regulatory enzymes

• coefficient partition

• substrate

Enzyme rate depends on...

• enzyme concentration

• water availibility

• heat

• substrate concentration

Regulation of enzyme activity is mediated by two mechanisms:

• control of catalytic efficiency through protein modification

• tissue need

• blood flow

• bioavailability

Select all of the following ways enzymes are regulated.

• amount of enzyme present

• Allosteric control

• reversible covalent modification

• isozymes

• proteolytic activation

Effectors that non-covalently bind to an enzyme that cause conformational change.

• allosteric activators and inhibitors

• substrate

• ions only

• water molecules

Allosteric site on an enzyme is

• within the active site

• separate from the active site

• the same at the active site

• can be in the active site or outside of the active site

Enzymes that usually have interactive subunits and have quaternary structure.

• conformational change

• allosteric enzymes

• Isozymes