The islets of the pancreas have different groups of cells known as alpha cells, beta cells, and gamma cells each one secreting different hormones.
The beta cells of the pancreas secret a hormone known as insulin.
Insulin secreted by the beta cells of the pancreas regulates the level of glucose in the blood.
Hyposecretion of insulin caused by the malfunction of beta cells causes a condition of increased blood sugar level than normal known as diabetes mellitus.