Why is oxygen needed for the electron transfer phosphorylation?

Question

I understand that oxygen is the acceptor of electrons and hydrogen ions during the electron transfer phosphorylation, the last step off the ATP-producing aerobic respiration.But why?Aren't there any other alternatives for this acceptor? Oxygen is already recognized to have several harmful effects to cells - wouldn't another molecule be a better choice?Why does it even require an "*acceptor*" to accept the electrons and hydrogen ions? What would happen if they were left alone?I apologize if my question was due to my ignorance in basic chemistry or biology, but do please point it out and explain it to me. Thanks!

Answer 1

There are other alternatives to oxygen as an acceptor. However, because oxygen can be eliminated from cells and can be recycled through plant's photosynthetic reactions, evolution has chosen oxygen as the acceptor. Exactly why this mechansim was chosen remains a question for many branches of biology and biochemistry.

The reason for the need for an acceptor is to have a final place for the electrons during the electron transfer phosphorylation. If a cell did not have this acceptor, this process would be void and life would not exist.

More so in freshman biology than freshman chemistry, the details of this process will be discussed. The exact mechanisms of this process will be heavily studied in a Biochemistry course.