In Year 9 Science students have been learning about biology with a focus on mammal body systems and homeostasis. This week we have looked at respiration. We completed experiments to reinforce the idea that humans breath in oxygen and breath out carbon dioxide by using new clean straws to blow into water and bromothymol blue indicator. We also completed an experiment with yeast and sugar so that we could witness the production of carbon dioxide through anaerobic respiration which occurs in animal cells when there is not enough oxygen available.