Enzymes usually function best at an optimal pH and temperature. The following graph shows the effectiveness of two enzymes at various temperatures. (b) One of these enzymes is found in humans and the other in thermophilic (heat-loving) bacteria. Which enzyme would you predict comes from which organism?

Verified step by step guidance

1. Examine the graph to identify the temperature range where each enzyme shows peak activity.
2. Recognize that human enzymes typically have optimal activity around human body temperature, approximately 37°C.
3. Identify the enzyme that shows peak activity around 37°C and predict that this enzyme is likely from humans.
4. Understand that thermophilic bacteria thrive in high-temperature environments, often above 50°C.
5. Identify the enzyme that shows peak activity at higher temperatures, such as 50°C or above, and predict that this enzyme is likely from thermophilic bacteria.

Key Concepts

Enzyme Activity and Optimal Conditions

Enzymes are biological catalysts that accelerate chemical reactions in living organisms. Each enzyme has an optimal pH and temperature range where it functions most effectively. Deviations from these conditions can lead to decreased activity or denaturation, where the enzyme loses its functional shape.

Thermophilic Enzymes

Thermophilic enzymes are produced by organisms that thrive in high-temperature environments, such as certain bacteria. These enzymes are adapted to maintain their structure and function at elevated temperatures, often exhibiting higher stability and activity compared to enzymes from mesophilic organisms, which prefer moderate temperatures.

Human Enzymes

Human enzymes are typically adapted to function optimally at the physiological conditions of the human body, which is around 37°C (98.6°F) and a neutral pH of approximately 7.4. These enzymes are crucial for various metabolic processes and are sensitive to changes in temperature and pH, which can affect their activity and stability.