Enzymes

Why do chemical reactions need to be controlled?

Why do chemical reactions need to be controlled?

To get the right amount of substrate and product at the right time, ensuring efficiency and preventing damage to cells.

How can you increase the speed of a reaction?

By increasing the concentration of substrates, raising the temperature, or using catalysts such as enzymes.

What is a catalyst?

a substance which increases the speed of reaction without being changed or used up in the reaction

What are the biological catalysts in humans?

enzymes

What is the use of enzymes in the human body?

Reduce the need for high temperatures, and to only speed up useful reactions in our body

What are enzymes?

large proteins / chains of amino acids folded into unique shapes

How do enzymes work?

The active site of an enzyme binds to a substrate, lowering the activation energy required for a reaction to occur.

What is the active site?

The unique shape of an enzyme that fits onto the substance involved in a reaction and allows the enzyme to catalyse the reaction effectively.

What is a substrate?

the substance an enzyme acts on

Explain the induced fit model of enzyme action.

The induced fit model suggests that the active site of an enzyme changes shape to better fit the substrate when they bind together, enhancing the enzyme's ability to catalyze the reaction.

Explain the lock and key model of enzyme action.

The lock and key model describes how the active site of an enzyme is precisely shaped to fit a specific substrate, similar to how a key fits into a lock, allowing for efficient catalysis.

How does temperature affect the rate of enzyme-catalyst reaction?

Temperature increases can enhance reaction rates up to a certain point, after which enzymes may denature and lose activity.

How does the pH affect the enzyme-catalyst reaction?

pH levels can significantly influence enzyme activity; each enzyme has an optimal pH range where it functions best, and deviations from this range can lead to decreased activity or denaturation.

What is the optimum pH for pepsin?

The optimum pH for pepsin is around 1.5 to 2, which is highly acidic, allowing it to function effectively in the stomach.

What is the usual pH level for enzymes?

The usual pH level for enzymes varies widely, but most enzymes function optimally at a neutral pH of around 7, while others may require more acidic or basic conditions.