3.The enzyme-substrate complex is formed when the substrate binds which part of the enzyme?

The enzyme-substrate complex is formed when the substrate binds to the active site of the enzyme.

Here are the steps:

1. The substrate approaches the enzyme: The substrate is the molecule that the enzyme will act upon.

2. The substrate binds to the enzyme's active site: The active site is a specific region on the enzyme where the substrate binds. This region has a specific shape and chemistry that fits the substrate molecule.

3. The enzyme-substrate complex is formed: Once the substrate is bound to the active site, the enzyme-substrate complex is formed. This is a temporary state where the enzyme is bound to its substrate.

4. The enzyme catalyzes the reaction: The enzyme then catalyzes a chemical reaction on the substrate. This can involve breaking down the substrate, or combining it with another molecule.

5. The products are released: After the reaction, the products are released from the enzyme. The enzyme is then free to bind with another substrate and repeat the process.