Discuss hemoglobin relative to its chemical structure, its function, and the color changes it undergoes during loading and unloading of oxygen.

Video transcript

Hey, everyone. Let's take a look at this question together which of the following statements best explains why hemoglobin changes color. Is it answer choice. A due to the presence of carboxy hemoglobin. Answer choice B due to changes in the P H levels. Answer choice C due to the presence of plasma proteins such as globulin or answer choice D due to the change in the electronic state of the iron in the heme group as it binds to or releases oxygen. Let's work this problem out together to try to figure out which of the following answer choices best explains why hemoglobin changes color. So we can recall that one of the main roles of hemoglobin is for oxygen to bind to it. And when oxygen binds to hemoglobin, the iron atom in the heme group undergoes a change in its electronic state. And as a result of that change, the protein color also changes. And when we say that the protein color changes, we are referring to when oxygen is bound to the hemoglobin, the color of the protein is bright red, which we can see in the oxygenated blood. However, when the oxygen is not bound to the hemoglobin. The color that we see in the protein is more of a darker, slightly blue I red when compared to that bright red. And this is the color that we see in the deoxygenated blood, which means that the change in color of hemoglobin is a result of oxygen either being bound to the hemoglobin or not bound, which is a result of that change in the electronic state. Making answer choice D due to the change in the electronic state of the iron in the heme group as it binds to oxygen or releases oxygen is the correct answer. And we know that answer choice A and B are incorrect. Since answer choice A and B only affect the way that hemoglobin binds to oxygen but do not directly cause that change in the protein color. And answer choice C is incorrect since the presence of plasma proteins does not directly affect the color leaving us with answer choice D I hope you found this video to be helpful. Thank you and goodbye.