The Circulatory and Respiratory Systems

You may be surprised to find that some animals, like jellyfish, do not have circulatory or respiratory systems. How do you think they survive without these functions? Jellyfish use diffusion to process oxygen and nutrients throughout their bodies.

Different than jellyfish, humans have complex circulatory and respiratory systems that work together to exchange gases, transport nutrients throughout the body, and maintain homeostasis.

Before you learn about the human circulatory and respiratory systems, examine the picture below to see if you can identify any of the following structures: arteries, diaphragm, heart, larynx, lungs, trachea, and veins. Then, hover your cursor over the image to see if you were correct. In this topic, you will learn about these structures and several others that make up the circulatory and respiratory systems.