GLOSSARY

Endocrine Homeostasis
Endocrine homeostasis is the dynamic regulation of internal conditions through hormonal signals. Controlled variables such as glucose, ionized calcium and extracellular osmolality fluctuate within functional limits rather than remaining perfectly constant.

A coordinated correction

When blood glucose increases after food, insulin secretion changes tissue uptake and storage. When glucose falls, insulin decreases and counterregulatory mechanisms become important. The measured variable and the hormone controlling it are different parts of the system.

Why the target can move

Sleep, meals, pregnancy and physical activity modify regulatory priorities and response patterns. A temporary shift can be appropriate to the situation. Persistent disturbance requires assessment of the control system, its target tissues and the external demand.

An exercise example

During sustained activity, lower circulating insulin can coexist with greater glucose uptake by contracting muscle. This illustrates coordinated regulation rather than failure of glucose control. Fluid shifts and carbohydrate availability also influence the pattern observed.