Myoglobin has a special function in muscle tissue. It a. breaks down glycogen, b. is a contractile protein, c. holds a reserve supply of oxygen in the muscle.

Video transcript

Hi, everybody. Let's look at our next question. Which of the following statements is true regarding myoglobin. A myoglobin requires high oxygen tension for oxygen release. B, myoglobin requires low oxygen tension for oxygen release C the oxygen release is unaffected by myoglobin affinity or D none of these. So let's think about some facts regarding myoglobin. Remembering that we do have that none of these option. That it might be that none of these statements is correct. Well, we are probably not going to have our answer be none of these because our first two answer choices are opposites. So odds are one will be correct and one will be incorrect. So we want to think about the oxygen tension in the environment and what that means for the oxygen release by myoglobin. And myoglobin stores oxygen in muscle tissue. And its role is to provide oxygen when it's needed for endurance. W with muscle tissues are using oxygen as they start to deplete it. Myoglobin is there with stored oxygen to help the muscles keep going. So you want myoglobin to be able to release oxygen when the levels of oxygen are low. And indeed, that is how it works. Choice B is correct. Myoglobin requires low oxygen tension for oxygen release. Myoglobin is used for oxygen storage. So when oxygen tension is high, myoglobin hangs on to the oxygen storing oxygen in oxygen rich environments and releasing it when oxygen levels are low. So choice A is incorrect. Choice D none of these is also incorrect since we have an answer here and finally, choice C the oxygen release is unaffected by myoglobin affinity. Um This would not be correct because my glob's high affinity for oxygen means it has to have just the right conditions for release. It must have low oxygen tension before it will release the oxygen. In addition, we recall that myoglobin has a higher affinity for oxygen than hemoglobin. And this is how it manages to get oxygen from hemoglobin. Hemoglobin require. We recall is used for oxygen transport, gets oxygen from the lungs. Hemoglobin is in the blood red blood cells and transports that oxygen around the body, but it has to be able to transfer the oxygen to the myoglobin for storage. So myoglobin higher affinity for oxygen means that can happen. So choice C is incorrect because myoglobin affinity for oxygen does matter to its the circumstances in which it will release oxygen. So again, our true statement regarding myoglobin is choice B, myoglobin requires low oxygen tension for oxygen release. See you in the next video.