We drew the outline of a body, adding the heart, lungs and kidneys. We made sure they were in the right position, then added blood vessels to show oxygenated and deoxygenated blood. We found out that all blood is red and the blue is only used on diagrams to show deoxygenated blood. We learnt that the circulatory system is a closed circuit, and blood keeps passing around it. Ennis 6 enjoyed singing the Circulatory System song.