Final answer:
The statement that the systemic circuit contains only oxygen-rich blood is false. Systemic circuit includes both oxygen-rich blood delivered to the body's tissues and oxygen-poor blood returning to the heart.
Step-by-step explanation:
The statement that the systemic circuit contains oxygen-rich blood only is false. In the systemic circuit, oxygen-rich blood is carried away from the heart to the body's organs and tissues, where oxygen is exchanged for carbon dioxide. The now oxygen-poor blood returns to the heart through the veins, specifically entering through the inferior vena cava and the superior vena cava, completing the systemic circulation before heading to the pulmonary circuit for reoxygenation. Therefore, the systemic circuit contains both oxygen-rich and oxygen-poor blood at different points in the circulation.