Enzymes usually function best at an optimal pH and temperature. The following graph shows the effectiveness of two enzymes at various temperatures. 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 provided in the problem. Identify the temperature ranges where each enzyme shows peak effectiveness. Note the temperature at which each enzyme performs optimally.
2. Recall that human enzymes typically function best at body temperature, which is approximately 37°C. Thermophilic bacteria enzymes, on the other hand, are adapted to high-temperature environments and usually function optimally at temperatures above 50°C.
3. Compare the optimal temperature of each enzyme from the graph to the expected temperature ranges for human enzymes and thermophilic bacteria enzymes. Match the enzyme with the organism based on this comparison.
4. Consider the broader biological context: enzymes from thermophilic bacteria are structurally adapted to withstand high temperatures without denaturing, while human enzymes are adapted to function in moderate temperatures typical of the human body.
5. Conclude which enzyme corresponds to humans and which corresponds to thermophilic bacteria based on the temperature data and biological reasoning.

Key Concepts

Enzyme Functionality

Enzymes are biological catalysts that speed up chemical reactions in living organisms. Their activity is highly dependent on environmental conditions, particularly pH and temperature. Each enzyme has an optimal range where it performs best, and deviations from this range can lead to decreased activity or denaturation.

Thermophilic Enzymes

Thermophilic enzymes are produced by organisms that thrive in high-temperature environments, such as certain bacteria. These enzymes are adapted to function efficiently at elevated temperatures, often exhibiting increased 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 temperature of around 37°C (98.6°F) and a neutral pH. These enzymes are crucial for various metabolic processes and are sensitive to changes in temperature and pH, which can affect their structure and function.