: 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.
1 The pancreas produces insulin in response to the presence of high levels of glucose in the blood. 2  Insulin stimulates cells, particularly in the liver and skeletal muscles, to absorb glucose from the blood and use it as an energy source or store it as glycogen.