A-Level Biology

Single and Double Circulatory Systems

In this video, we look at single and double circulatory systems. First, we look at single circulatory systems such as that found in fish. We then explore the double circulatory system for example the one found in humans. Finally, for OCR students, we look at what is meant by a closed circulatory system (eg in humans and fish) and an open circulatory system (eg in insects).