Excretion and Osmoregulation
Insect faeces, either in liquid form or solid pellets, contains both undigested food
and metabolic excretions. Aquatic insects excrete dilute wastes from their anus directly
into water by flushing with water. But, Terrestrial insects must conserve water. This
requires efficient waste disposal in a concentrated or even dry form, simultaneously
avoiding the toxic effects of nitrogen. Both terrestrial and aquatic insects must conserve
ions, such as sodium (Na
+
), potassium (K
+
) and chloride (Cl
-
), that may be limiting in their
food or lost into the water by diffusion. Therefore the production of insect excreta (urine or
pellets) is a result of two related processes:
Dostları ilə paylaş: