Homeostasis is a state of relative stability and regulation of the internal condition of cells and organisms. These internal conditions include temperature, water, and sugar levels. Homeostasis allows the cell or organism to function at an optimal level, even when challenged by internal and external changes.You and Your Hormones from the Society for Endocrinology. (n.d.). Homeostasis. [online] Available at: http://www.yourhormones.info/students/topics/homeostasis/ [Accessed 15 Nov. 2018].