Basics of Enzymes

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What are enzymes?

Enzymes are proteins that act as biological catalysts, speeding up chemical reactions in living organisms.

What is the active site of an enzyme?

The active site is the region on an enzyme where substrate molecules bind and undergo a chemical reaction.

What is a substrate in enzyme activity?

A substrate is the specific reactant that an enzyme acts upon during a biochemical reaction.

How do enzymes lower activation energy?

Enzymes lower activation energy by stabilizing the transition state, making it easier for the reaction to occur.

What is an example of an enzyme and its function?

Amylase is an enzyme that helps break down starch into sugars during digestion.

How is enzyme activity affected by temperature?

Enzyme activity increases with temperature up to a point but can denature and lose function if the temperature is too high.

What is denaturation in the context of enzymes?

Denaturation is the process where an enzyme loses its shape and, consequently, its function due to factors like pH or temperature changes.

How does pH affect enzyme activity?

Each enzyme has an optimal pH range where it functions best, and extreme pH levels can denature the enzyme.

What are enzyme inhibitors?

Enzyme inhibitors are molecules that bind to enzymes and decrease their activity.

What is a cofactor?

A cofactor is a non-protein chemical that assists enzymes in performing their catalytic activity.

What is a coenzyme?

A coenzyme is an organic non-protein compound that binds to an enzyme and is necessary for its activity.

What is enzyme specificity?

Enzyme specificity is the concept that each enzyme only catalyzes one kind of reaction or acts on a specific substrate.

What is the importance of enzymes in metabolism?

Enzymes are crucial for metabolism as they regulate the speed of chemical reactions necessary for life processes.

What is the lock and key model?

The lock and key model suggests that the enzyme's active site is exactly complementary to the shape of the substrate.

What is the induced fit model?

The induced fit model proposes that enzyme active sites are flexible and change shape to bind more precisely with the substrate.





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1. What are enzymes?

Enzymes are proteins that act as biological catalysts, speeding up chemical reactions in living organisms.

Enzymes are carbohydrates used to store energy in cells.

Enzymes are vitamins that help in the digestion of fats.

2. What is the active site of an enzyme?

The active site is the region on an enzyme where substrate molecules bind and undergo a chemical reaction.

The active site is where inhibitors bind to stop the enzyme activity.

The active site is a term used to describe the gene responsible for enzyme production.

3. What is a substrate in enzyme activity?

A substrate is the specific reactant that an enzyme acts upon during a biochemical reaction.

A substrate is the byproduct formed after an enzyme's catalytic action.

A substrate is a high-energy molecule stored in cells before enzyme action.

4. How do enzymes lower activation energy?

Enzymes lower activation energy by stabilizing the transition state, making it easier for the reaction to occur.

Enzymes lower activation energy by providing energy to substrates to jump to higher energy levels.

Enzymes lower the temperature of the reaction environment to reduce energy needs.

5. What is an example of an enzyme and its function?

Amylase is an enzyme that helps break down starch into sugars during digestion.

Lactase is an enzyme that assists in the digestion of lactose by converting it into amino acids.

Protease is an enzyme that catalyzes the polymerization of nucleotides in DNA synthesis.

6. How is enzyme activity affected by temperature?

Enzyme activity increases with temperature up to a point but can denature and lose function if the temperature is too high.

Enzyme activity is not affected by temperature changes, as they are stable at all temperature levels.

Higher temperature invariably leads to increased enzyme activity without any loss of efficiency.

7. What is denaturation in the context of enzymes?

Denaturation is the process where an enzyme loses its shape and, consequently, its function due to factors like pH or temperature changes.

Denaturation is a reversible adjustment of enzyme shape that enhances catalytic efficiency.

Denaturation involves the enzyme acquiring a new, more stable structure to improve activity.

8. How does pH affect enzyme activity?

Each enzyme has an optimal pH range where it functions best, and extreme pH levels can denature the enzyme.

pH does not affect enzyme activity as they adapt to any pH level.

Enzymes work most effectively at any pH level below 4.

9. What are enzyme inhibitors?

Enzyme inhibitors are molecules that bind to enzymes and decrease their activity.

Enzyme inhibitors are catalysts that increase enzyme activity by altering their structure.

Enzyme inhibitors convert enzymes into coenzymes during metabolic reactions.

10. What is a cofactor?

A cofactor is a non-protein chemical that assists enzymes in performing their catalytic activity.

A cofactor is a type of enzyme that increases reaction rates by lowering pH.

A cofactor is a protein component permanently attached to enzymes during synthesis.

11. What is a coenzyme?

A coenzyme is an organic non-protein compound that binds to an enzyme and is necessary for its activity.

A coenzyme is the inactive form of an enzyme that becomes active only after phosphorylation.

A coenzyme is a metallic ion facilitating enzyme activity under acidic conditions.

12. What is enzyme specificity?

Enzyme specificity is the concept that each enzyme only catalyzes one kind of reaction or acts on a specific substrate.

Enzyme specificity refers to the enzyme's ability to change shape to adapt to any substrate.

Enzyme specificity is the ability of enzymes to catalyze reactions at specific temperatures.

13. What is the importance of enzymes in metabolism?

Enzymes are crucial for metabolism as they regulate the speed of chemical reactions necessary for life processes.

Enzymes only play a minor role in metabolism by storing energy in cells.

Enzymes are not involved in metabolism but in building cellular structures.

14. What is the lock and key model?

The lock and key model suggests that the enzyme's active site is exactly complementary to the shape of the substrate.

The lock and key model proposes that enzymes can open molecular locks within cells.

The lock and key model refers to the physical barrier enzymes create to prevent substrates from reacting.

15. What is the induced fit model?

The induced fit model proposes that enzyme active sites are flexible and change shape to bind more precisely with the substrate.

The induced fit model explains how enzymes are induced to work faster by increased temperature.

The induced fit model describes the enzyme's ability to break substrate molecules instantly without energy input.