What do you mean by Km-value ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Km-value**: Km-value, or Michaelis constant, is a key concept in enzyme kinetics. It provides insight into the affinity of an enzyme for its substrate.

2. **Graph Representation**: To understand Km, we often refer to a velocity vs. substrate concentration graph. In this graph:
- The x-axis represents substrate concentration.
- The y-axis represents the reaction velocity (rate of product formation).

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