Final answer:
Reticulocytes are immature red blood cells that mature into erythrocytes, whose function is to transport oxygen throughout the body, making option 1 the correct choice.
Step-by-step explanation:
Reticulocytes are immature red blood cells (RBCs) that are released from the bone marrow into the bloodstream. Their primary function is to mature into erythrocytes, which are fully developed red blood cells responsible for transporting oxygen throughout the body. This maturation process typically occurs within the first day or two of the reticulocyte entering the circulation, during which time the reticulocyte may still contain fragments of organelles. Once mature, erythrocytes are specialized cells that do not contain a nucleus or mitochondria and are equipped with hemoglobin, a protein that binds oxygen, allowing RBCs to deliver oxygen to the cells and remove carbon dioxide.
To answer the student’s question, the function of reticulocytes is to transport oxygen, making option 1 the correct choice.