What is the main role of insulin in the body?

Insulin plays a crucial role in regulating blood sugar levels in the body. Produced by the pancreas, it allows cells to absorb glucose from the bloodstream, which is essential for energy production. When we eat, carbohydrates are broken down into glucose, and insulin is released in response to increase blood sugar levels. This hormone facilitates the uptake of glucose by cells, which lowers blood sugar levels to a normal range, preventing hyperglycemia. Additionally, insulin aids in the storage of excess glucose in the liver and muscle tissue for later use, ensuring that energy is available to the body when needed.

The other options do not accurately depict the primary function of insulin. Blood pressure regulation is primarily the role of hormones such as aldosterone and angiotensin. Muscle growth is influenced by different factors, including hormones like testosterone and growth hormone, rather than insulin directly. Likewise, immune function is largely supported by various immune cells and cytokines rather than insulin. Thus, the primary and most significant function of insulin is indeed the control of blood sugar levels.