Question

hemoglobin is a protein that binds to oxygen. it is only produced by red blood cells and it allows blood to transport oxygen throughout the body. what statement does this information best demonstrate?
a. proteins in specialized cells are the result of the expression of particular genes.
b. proteins with similar functions to those produced in humans can be found in other species.
c. specialized cells that are grouped together and perform similar functions are called tissues.
d. the proteins produced by cells have structures that are related to their function.

Explanation:

• Option A: The info is about hemoglobin's production in red blood cells and its function, not about gene expression for proteins in specialized cells. Eliminate A.
• Option B: The passage doesn't mention other species or proteins with similar functions in them. Eliminate B.
• Option C: The text is about hemoglobin (a protein) and red blood cells, not about tissues (groups of specialized cells). Eliminate C.
• Option D: Hemoglobin is a protein produced by red blood cells, and its structure allows it to bind to oxygen (function - transporting oxygen). This shows the structure of the protein is related to its function. So D matches.

Answer:

D. The proteins produced by cells have structures that are related to their function.