Question

hemoglobin is a protein found in the red blood cells of vertebrates (organisms with a backbone) and the plasma (body fluid) of many invertebrates. the function of this protein is to transport oxygen throughout the organism and to bring back carbon dioxide to be expelled. if the amino acid sequence of the protein is altered, like in sickle cell anemia, the mutated protein is not as efficient at carrying oxygen. which argument is supported by this information? sickle cell anemia sickle cell normal red blood cell normal hemoglobin must be a larger molecule that the mutated hemoglobin since it has sufficient space to attach to and carry both oxygen and carbon dioxide molecules. structural changes in hemoglobin affect its ability to carry oxygen, indicating that the shape of the protein is important to its function. hemoglobin must be a simple molecule because it is found in both vertebrates and invertebrates. the mutated hemoglobin can still carry carbon dioxide to be expelled by the organism.

Explanation:

The text states that when the amino - acid sequence of hemoglobin (a structural change) is altered in sickle cell anemia, the protein is less efficient at carrying oxygen. This shows that the shape of the protein (altered by the amino - acid sequence change) affects its function. There is no information about the size comparison between normal and mutated hemoglobin, nor does the text suggest that hemoglobin is a simple molecule because it is found in different organisms. Also, there is no mention of the mutated hemoglobin's ability to carry carbon dioxide.

Answer:

Structural changes in hemoglobin affect its ability to carry oxygen, indicating that the shape of the protein is important to its function.