Final answer:
Islet cells in the pancreas secrete hormones such as insulin and glucagon which play critical roles in regulating blood glucose and metabolic functions. Alpha, beta, delta, and gamma cells each produce different hormones with specific regulatory actions.
Step-by-step explanation:
The sentence, when completed with the correct scientific terminology, reads as follows: Islet pancreatic cells secrete insulin, glucagon, somatostatin, or pancreatic polypeptide hormones that regulate blood glucose levels and other important metabolic processes.
These hormones are secreted by distinct types of cells within the pancreatic islets: alpha cells secrete glucagon, which increases blood glucose; beta cells secrete insulin, which decreases blood glucose; delta cells secrete somatostatin, which inhibits the release of other hormones; and gamma cells secrete pancreatic polypeptide, which helps regulate exocrine and endocrine secretions of the pancreas.