When pH or temperature is plotted against enzyme activity the shape of curve obtained is

Options

A. A parabola
B. A bell shaped curve
C. A rectangular hyperbola
D. A sigmoid curve

Answer

To solve the question about the shape of the curve obtained when pH or temperature is plotted against enzyme activity, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Enzyme Activity**: Enzymes are biological catalysts that speed up chemical reactions in the body. Their activity can be influenced by various factors, including pH and temperature.

2. **Effect of pH on Enzyme Activity**: Each enzyme has an optimal pH at which it functions best. Deviations from this optimal pH can lead to a decrease in enzyme activity.

3. **Effect of Temperature on Enzyme Activity**: Similarly, enzymes have an optimal temperature range. Below or above this range, the activity of the enzyme decreases, often leading to denaturation at high temperatures.

4. **Graphing the Relationship**: When we plot enzyme activity against pH or temperature, we observe that the activity increases to a maximum point and then decreases. This results in a curve that resembles a bell shape.

5. **Identifying the Curve Shape**: The curve obtained from this relationship is typically described as a bell-shaped curve, which looks like an inverted U. This indicates that there is an optimal pH or temperature for enzyme activity.

6. **Conclusion**: Therefore, when pH or temperature is plotted against enzyme activity, the shape of the curve obtained is a bell-shaped curve.

### Final Answer:
The shape of the curve obtained when pH or temperature is plotted against enzyme activity is a **bell-shaped curve**.

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