What role does glucagon play in relation to insulin?

Glucagon plays a critical role in glucose metabolism by acting as a counter-regulatory hormone to insulin, primarily managing blood sugar levels by increasing them when necessary. Its primary function is to stimulate the liver to convert stored glycogen into glucose, which is then released into the bloodstream, thereby raising blood glucose levels.

The choice indicating that glucagon "brings insulin out of storage" aligns with the understanding that glucagon can influence insulin secretion from the pancreas. When blood sugar levels drop, glucagon initiates processes that signal the pancreas to release stored insulin, helping to balance glucose levels in the body. This response is part of the complex feedback system that regulates blood glucose concentration.

The other options do not accurately reflect the role of glucagon. For instance, decreasing blood sugar levels, stimulating insulin production directly, or inhibiting sugar metabolism are functions more aligned with insulin itself rather than glucagon. Understanding glucagon’s role emphasizes its importance in maintaining glucose homeostasis opposite to that of insulin.