Search results
Results from the WOW.Com Content Network
The Malpighian tubule system is a type of excretory and osmoregulatory system found in some insects, myriapods, arachnids and tardigrades. It has also been described in some crustacean species, [ 1 ] and is likely the same organ as the posterior caeca which has been described in crustaceans.
Malpighian tubules secrete primary urine, most of which is passed into the hindgut where water, ions and essential metabolites are reabsorbed before the fluid is excreted. Excretion is under the control of diuretic and anti-diuretic factors, or hormones .
Malpighi's name is borne by several physiological features related to the biological excretory system, such as the Malpighian corpuscles and Malpighian pyramids of the kidneys and the Malpighian tubule system of insects. The splenic lymphoid nodules are often called the "Malpighian bodies of the spleen" or Malpighian corpuscles.
A renal corpuscle (or Malpighian body [1]) is the blood-filtering component of the nephron of the kidney. It consists of a glomerulus - a tuft of capillaries composed of endothelial cells - and a glomerular capsule known as Bowman's capsule .
The Malpighian tubules are not free in the hemocele but are bound to the wall of the rectum by the perinephric membrane. This structure allows efficient resorption of water from diuresis and absorption of atmospheric water that is present in the hindgut as humidity. An adaptation for water conservation. [1] [2]
Polytene chromosomes are present in secretory tissues of dipteran insects such as the Malpighian tubules of Sciara and also in protists, plants, mammals, or in cells from other insects. Some of the largest polytene chromosomes described thus far occur in larval salivary gland cells of the chironomid genus Axarus.
To conserve water, air-breathing chelicerates excrete waste as solids that are removed from their blood by Malpighian tubules, structures that also evolved independently in insects. [3] While the marine horseshoe crabs rely on external fertilization, air-breathing chelicerates use internal but usually indirect fertilization.
Malpighian tubule: any of the excretory organs in insects that lie in the abdominal body cavity and empty into the junction between the midgut and hindgut [6] Mesonephric tubule: tubules comprising the mesonephros or temporary kidney of amniotes; Metanephric tubule: tubules comprising the permanent kidney of amniotes [4]