Factors Affecting Enzymes

Questions and Answers

What happens to enzyme activity as temperature rises towards the optimum?

The kinetic energy of molecules increases. (correct)

The reaction rate decreases.

The enzyme becomes denatured immediately.

The enzyme activity remains constant.

What is the result of an enzyme being denatured?

The shape of the active site changes. (correct)

The enzyme increases its activity.

The pH of the enzyme remains constant.

The enzyme becomes more effective.

Which of the following statements is true about most enzymes?

They typically work best at a neutral pH of 7. (correct)

They are denatured at their optimum temperature.

They have an optimum temperature of 40°C.

They work best at a pH lower than 7.

At what temperature do enzymes in the human body work optimally?

37°C Signup and view all the answers

What pH level do most enzymes prefer for optimal activity?

pH 7 Signup and view all the answers

Which of the following correctly describes the effect of temperature on enzyme activity?

Enzyme activity increases until the optimum, then declines sharply. Signup and view all the answers

Why do some bacteria have enzymes that perform best at lower temperatures?

They have evolved in cold environments. Signup and view all the answers

What occurs when the pH moves away from an enzyme's optimum level?

The active site changes shape, affecting substrate binding. Signup and view all the answers

Study Notes

Enzyme Activity Factors

'Optimum' temperature is the temperature at which enzyme reactions occur most rapidly.
Kinetic energy increases with temperature, enhancing enzyme and substrate movement and collision rates.
Enzyme concentration and substrate concentration both accelerate reaction rates.

Temperature Effects

Enzymes in the human body function best at 37°C (body temperature).
A graph of reaction rate versus temperature reveals a peak, indicating optimum temperature.
As temperature rises to the optimum, the reaction rate increases due to higher kinetic energy.
Temperatures above 40°C can denature enzymes, permanently altering active sites.
Denaturation is analogous to cooking an egg, where proteins lose their structure when heated.
Not all enzymes have an optimum temperature of 37°C; adaptation to the organism's normal body temperature is common.
Bacteria with an average habitat of 10°C likely have enzymes optimized for that temperature.

pH Effects

The ideal pH for most enzymes is around neutral (pH 7).
Enzyme activity decreases significantly at extreme pH levels, creating a bell-shaped curve in activity versus pH graphs.
The enzyme's optimal pH is where it performs most efficiently; deviations can alter the enzyme’s structure and active site shape.
Exceptions exist where some enzymes function optimally at non-neutral pH levels.
Stomach enzymes often have acid tolerance, enabling functionality in highly acidic conditions caused by hydrochloric acid.

Description

This quiz explores the various factors that influence enzyme activity, including temperature and concentration. Understand how these elements impact the speed of enzyme reactions and the role of kinetic energy. Test your knowledge about enzymes and their optimal conditions.