If a red blood cell is 100% saturated, how many molecules of o2 are bound to it? 1 billion molecules of o24 molecules of o2250 million molecules of o2?

1 billion molecules O₂

Explanation:

From my research, a human red blood cell contains approximately 270 million hemoglobin molecules.    

A hemoglobin molecule contains four heme groups, each of which has an iron ion forming a coordination complex that carries every dioxygen molecule. Therefore for each hemoglobin molecule, we will have 4 dioxygen molecules. The heme groups are responsible for the transport of every dioxygen and other diatomic gases.                    

Hence, the number of O₂ molecules in a red blood cell saturated with 100% will be:                

So, the correct answer is 1 billion of O₂ molecules.  

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