Learn: Factors Affecting Enzyme Activity

Welcome!Great to see you back! You've already learned about enzymes as biological catalysts and their role in speeding up reactions. Today, we'll explore the factors that affect how enzymes work, like temperature, pH, and concentration.

What is enzyme activity?Enzyme activity refers to how quickly an enzyme helps a reaction happen. It depends on conditions like temperature, pH, and substrate concentration. These factors influence the enzyme's ability to bind with its substrate and form a product.

How temperature affects enzyme activityEnzymes work best at an optimum temperature, often around body temperature (37°C in humans). Too low, and molecules move slowly, reducing collisions. Too high, and the enzyme denatures (loses its shape), stopping activity.

How pH affects enzyme activityEnzymes also have an optimum pH, which varies by enzyme. For example, pepsin works best in acidic conditions (pH 2) in the stomach. If the pH is too high or low, the enzyme's shape changes, reducing activity.

How substrate concentration affects enzyme activityAt low substrate concentration, enzyme activity is limited because there aren't enough substrates to bind. As concentration increases, activity rises until all active sites are occupied. Beyond this, adding more substrate won't increase activity.

Review Time!Well done! You've learned how temperature, pH, and substrate concentration affect enzyme activity. Now let's test your understanding with a few questions.

Final ThoughtsGreat work today! You've mastered the factors affecting enzyme activity. Remember, enzymes are sensitive to their environment, and changing conditions can either enhance or stop their function. Keep exploring science!