The electron-transport chain uses several different metal ions, especially iron, copper, zinc, and manganese. Why are metals used frequently in these two pathways? What can metals do better than organic biomolecules?

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All right. Hello everyone. So this question is asking us to determine if the statement is true or false considering the different metal ions, especially iron copper, zinc and manganese. The mentioned metal ions do not survey function in the electron transport chain and ATP synthesis explain your answer. So first and foremost, what is the electron transport chain? And what drives ATP synthesis? Let's recap. So here what I'm drawing right now are the two membranes present in mitochondria. We have the outer membrane at the top and the inner membrane on the bottom. So because we have two membranes, we have this space between the two membranes known as the inter membrane space which makes sense. So what's important here is first the electron transport chain. So the electron transport chain involves four protein complexes that are embedded within the inner mitochondrial membrane. So this is a simplified drawing here of these four, these four membrane proteins. So within these protein complexes, a series of redox reactions are taking place, redox reactions is a collective term for oxidation and reduction. So basically, we're concerned with the transfer of electrons from one species to another. In any case though as a result of these redox reactions. What happens is that a proton gradient is established because what happens is that protons accumulate within this inter membrane space. And these protons within the inter membrane space play a key role in the synthesis of A TP. So for the synthesis of a TP, we have another protein within the, within the inter mitochondrial membrane that is not involved in the electron transport chain. And that is at P synthesis. So it's this large protein off to the side here that I'm shading in a little bit. So a TP synthesis essentially takes advantage of the proton gradient to produce a lot of ATP. So what's happening here? Well, as mentioned, a gradient is established, right, because there's a high concentration of protons within the intramembrane space. The instinct of these protons is to move to an area of lower proton concentration. In other words, to the mitochondrial matrix, the inside of the mitochondria. And so here in taking advantage of that proton or those protons desire to move these protons are funneled through AC P synthese as they move into the mitochondrial matrix. And in doing so ATP synthese produces ATP so it works out. So what does all this have to do with metal ions? Well, recall it earlier, we talked about the role of redox reactions in the electron transport chain in establishing the gradient in the first place. So when it comes to those redox reactions, right metal ions are essential and metal ions are essential in a plethora of metabolic pathways. They can even play a role in stabilizing species that have a charge to them. So what are some specific examples in the or with the metal ions that are mentioned here? Iron copper, zinc and manganese, while starting off with iron, right, iron is going to play a role in proteins that contain iron sulfur groups. So in the electron transport chain, specifically, we have iron in complexes one two and three. So complexes 12 and three of the electron transport chain contained iron sulfur groups. But recall that iron is also present in heme groups. And you can find heme groups in complexes three and four. So all four complexes of the electron transport chain have iron to some capacity. Now complex four specifically also contains copper and copper is actually involved in the final transport of electrons because after complex four, any remaining electrons are accepted by molecular oxygen which is then converted into water after reacting with hydrogen ions. So copper is involved in the final reduction of oxygen. Now, zinc in general plays a role in some dehydrogenase complexes. And as mentioned before plays a role in stabilizing certain enzymes of the electron transport chain. Manganese. On the other hand, is a cofactor in the enzyme that protects the mitochondria from reactive oxygen species. Why? Because during this process of oxygen accepting electrons, there's the possibility of radicals forming and if those radicals aren't neutralized and that can become dangerous later on. So that enzyme, the one that protects us from oxygen radicals does require manganese. So all this is to say right, that the statement given is not true, right. Metal ions play an essential role in not only catalyzing the transfer of electrons but also stabilizing certain species and behaving as a cofactor of essential enzymes. So with that said, I can scroll down here to reveal the answer that I had just offscreen. It reads that the statement is false. The mentioned metals are present in the electron transport chain and ATP synthesis, mainly functioning as reducing and oxidizing agents and there you have it. So with that being said, thank you so very much for watching and I hope you found this helpful.

The electron-transport chain uses several different metal ions, especially iron, copper, zinc, and manganese. Why are metals used frequently in these two pathways? What can metals do better than organic biomolecules?

Verified video answer for a similar problem:

Key Concepts

Electron Transport Chain (ETC)

Role of Metal Ions in Biochemical Reactions

Redox Reactions