What function does insulin serve in the body?

Insulin plays a crucial role in regulating blood sugar levels in the body. It is a hormone produced by the pancreas that helps cells absorb glucose from the bloodstream, thus lowering blood sugar levels after meals. When we eat, carbohydrates are broken down into glucose, which enters the bloodstream. In response, the pancreas releases insulin to facilitate the uptake of this glucose into cells for energy or storage as glycogen in the liver and muscle tissues.

This process is vital for maintaining homeostasis, as excessive glucose in the blood can lead to conditions such as hyperglycemia, while low blood sugar can cause hypoglycemia. By managing these levels, insulin supports overall metabolic functions and energy balance within the body.

The other options do not accurately describe a primary function of insulin, as digestion of proteins, control of sleep cycles, and stimulation of adrenal activity are governed by different mechanisms and hormones in the body.