: the bodily system that in vertebrates is made up of the brain and spinal cord, nerves, ganglia, and parts of the receptor organs and that receives and interprets stimuli and transmits impulses to the effector organs â compare central nervous system â autonomic nervous system, peripheral nervous system.
Insulin is produced by beta cells of the pancreatic islets in most vertebrates and by the Brockmann body in some teleost fish. Cone snails Conus geographus and Conus tulipa, venomous sea snails that hunt small fish, use modified forms of insulin in their venom cocktails.
There is no question that insulin causes weight gain. Insulin is a hormone secreted by the pancreas in response to sugar intake. Its role is to drive sugar into the cells of the body, where it is used as a source of energy (measured in calories). Insulin, therefore, pumps calories into cells.