Question

a student performed an experiment to determine the effect of temperature on the enzyme catalase found in the cells of potatoes. the enzyme catalase is present in a potato’s cells. when the student first added hydrogen peroxide (a toxic by - product of cellular respiration) to the potatoes, the potatoes then produced a gas (which is in each test tube) that caused a... to the potatoes. the catalase is being studied because it breaks down hydrogen peroxide into water and oxygen. the amount of bubbles (the gas is known which people breathe to live) the student... is the rate of the reaction (a rise in the occurrence of oxygen bubbles in the test tube). the student recorded the results in the graph shown. chart: catalase effectiveness, x - axis: temperature (°c) with values 15°c, 20°c, 25°c, 30°c, 35°c, 40°c, 45°c, 50°c; y - axis with some scale. which statement is best supported by the results? (read carefully) remember what enzymes are supposed to do! options:

• catalase has the most effectiveness at mild, high temperatures
• catalase works best when temperatures are above 70°c
• catalase has the same effectiveness at all temperatures
• catalase works best when temperatures are below 15°c

Explanation:

To determine the correct statement, we analyze the graph (Catalase Effectiveness vs. Temperature) and enzyme properties. Enzymes like catalase have an optimal temperature range. The graph likely shows catalase activity increasing with temperature up to an optimal point (around 50°C here, as the bar is tallest).

• Option 1: "Catalase has the most effectiveness at mild - high temperatures" – As temperature rises (mild to high, like up to 50°C), the bar height (effectiveness) increases, so this matches.
• Option 2: "Catalase works best when temperatures are above 70°C" – The graph doesn't show data above 50°C, and enzymes typically denature at very high temps, so this is wrong.
• Option 3: "Catalase has the same effectiveness at all temperatures" – The bar heights vary (e.g., 15°C bar is low, 50°C is high), so effectiveness differs, wrong.
• Option 4: "Catalase works best when temperatures are below 15°C" – The 15°C bar is low, so activity is not best here, wrong.

Answer:

A. Catalase has the most effectiveness at mild - high temperatures