Jul 17, 2019 · A Malpighian tubule is an anatomical structure found in the digestive system of insects that live on land. Usually, these tubules excrete solid waste products, creating an efficient way for the insect to expel toxins and products left over from the breakdown of the insect’s food. Malpighian tubule, in insects, any of the excretory organs that lie in the abdominal body cavity and empty into the junction between midgut and hindgut. In species having few malpighian tubules, they are long and coiled; in species with numerous (up to 150) tubules, they are short.
In malpighian tubules of insects, secretion from the cells forming the wall is the only mechanism for solute and water transport as ultrafiltration is not effective. Such cells are typically localized in the distal, blind-ended segment of the tubulus that secretes electrolytes, organic solutes, and water. The Malpighian tubule system is a type of excretory and osmoregulatory system found in some insects, myriapods, arachnids, and tardigrades. The system consists of branching tubules extending from the alimentary canal that absorbs solutes, water, and wastes from the surrounding hemolymph. The wastes then are released from the organism in the form of solid nitrogenous compounds and calcium oxalate. .
Malpighian tubules are found in the posterior regions of insects, where they work with glands in the rectum to excrete waste and maintain osmotic balance. Ions are transported through active pumps found in the malpighian tubules; as the ions are secreted, water and waste are drawn to the tubules due to the change in osmotic pressure. Feb 01, 2009 · In Drosophila, the adult Malpighian tubule is the key tissue for defence against insecticides such as DDT; and it can also detect and mount Cited by: 134.