Which organ is primarily responsible for producing insulin?

The pancreas plays a crucial role in the body's endocrine system by producing insulin, a hormone vital for regulating blood sugar levels. Insulin allows cells to absorb glucose from the bloodstream, which is essential for energy production. The pancreas contains specialized cells called beta cells, located in the islets of Langerhans, that specifically secrete insulin in response to rising glucose levels after eating. This regulation of glucose metabolism is critical for maintaining homeostasis in the body.

Other organs listed do not have the primary function of insulin production. The liver, for example, does play a significant role in glucose metabolism and storage but does not produce insulin. Instead, it is more involved in processes such as glycogen storage and gluconeogenesis, which help maintain blood sugar levels under different physiological conditions. The stomach is mainly responsible for digesting food and does not produce insulin, while the kidneys filter blood and have roles in electrolyte balance but do not have a direct function in insulin production.