Blood sugar regulation cells in the pancreatic islets are among the most well understood and important. If the blood glucose level falls to dangerous levels (as during very heavy exercise or lack of food for extended periods), the alpha cells of the pancreas release glucagon, a hormone whose effects on liver cells act to increase blood glucose levels. They convert glycogen into glucose (this process is called glycogenolysis). The glucose is released into the bloodstream, increasing blood sugar. Hypoglycemia, the state of having low blood sugar, is treated by restoring the blood glucose level to normal by the ingestion or administration of dextrose
Organ gifting follows Mauss' (1950) ideas of gift giving as a system of total services (production, distribution, and consumption) where self-interest interacts with social and moral obligations that are collectively imposed to maintain social relationships and guarantee the reproduction of society. Titmuss' work was very influential at a policy level. It motivated the Nixon administration in the U.S. to reform its system of blood donation and led many people in the U.K. to oppose models of marketable blood donation systems. This concept has been incorporated into the phrase "the gift of life" which was used to refer to multiple forms of organ,