The pancreas is classified as a gland that secretes which substance?

The pancreas is classified as an endocrine gland because it plays a crucial role in regulating blood sugar levels through the production and secretion of hormones. Insulin is one of the key hormones produced by the pancreas, specifically by the beta cells within the islets of Langerhans. After a meal, when blood glucose levels rise, insulin is secreted into the bloodstream to facilitate the uptake of glucose by cells for energy or storage as glycogen. This action is essential for maintaining homeostasis in the body.

In addition to insulin, the pancreas also secretes other hormones, such as glucagon, which works to raise blood sugar levels when they are too low. However, the primary reason for classifying the pancreas as an important gland in the context of this question is its role in insulin production. Thus, the production of insulin is foundational to the pancreas's endocrine function and its ability to regulate metabolic processes involving carbohydrates, fats, and proteins.