Insulin is a type of hormone. Produced by the pancreas, it plays a pivotal role in regulating blood sugar levels. When blood sugar levels rise, such as after a meal, insulin is released into the bloodstream. Insulin acts as a key that unlocks cells, allowing glucose from the bloodstream to enter and be utilized for energy production or stored for later use. This process helps to lower blood sugar levels, maintaining them within a healthy range.
Insulin deficiency or insensitivity can lead to diabetes mellitus, a condition characterized by elevated blood sugar levels. Without sufficient insulin action, cells cannot effectively utilize glucose, resulting in various metabolic complications.
Unlike salts, enzymes, or vitamins, insulin does not function primarily as a catalyst for chemical reactions, a nutrient, or an ion. Instead, it serves as a signaling molecule regulating glucose metabolism in the body. Therefore, the correct option is (b) Hormone.