Digestive enzymes of diverse specificities are found in the saliva secreted by the salivary glands, in the secretions of cells lining the stomach, in the pancreatic juice secreted by pancreatic exocrine cells, and in the secretions of cells lining the small and large intestines.
The range of temperatures in which an insect is able to live and reproduce is one element of that organism's niche, a description of its ecological requirements.
