How many oxygen molecules can be carried out by one haemoglobin molecule.

Explanation

To determine how many oxygen molecules can be carried by one hemoglobin molecule, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Hemoglobin Structure**: Hemoglobin is a protein found in red blood cells (RBCs) that is responsible for transporting oxygen. It has a specific structure that allows it to bind to oxygen molecules.

2. **Identify the Components of Hemoglobin**: Hemoglobin is made up of four polypeptide chains. Each of these chains contains an iron (Fe) atom, which is crucial for oxygen binding.

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