Answer:
D. Blood sugar (glucose)
Step-by-step explanation:
Blood sugar (glucose) is stored in the liver and muscles as glycogen. When blood sugar levels are too low, the body can break down glycogen to release glucose into the bloodstream to maintain normal blood glucose levels. However, if blood sugar levels are too high, excess glucose can cause damage to cells, such as red blood cells, leading to crenation (shrinking) or even bursting.
Maintaining normal blood sugar levels is crucial for homeostasis, which is the body's ability to maintain a stable internal environment despite external fluctuations. This is achieved through a complex system involving hormones, such as insulin and glucagon, which regulate blood sugar levels by promoting the uptake and storage of excess glucose or the release of stored glucose when needed.