The purpose of the malpighian tubule is to absorb and excrete the metabolic wastes that make up urine in arthropods. They actively absorb water, dissolved substances and waste from the surrounding body fluids to be released as solid nitrogen-based compounds.Continue Reading
The malpighian tubules absorb urea and amino acids very easily, but ions such as potassium and sodium are actively pumped in through their membranes. The tubules carry these wastes to the rectum, where water and ions are reabsorbed and the urea is mixed with feces to be excreted through the anus. Various species have specialized purposes for the malpighian tubules beyond these basic functions. New Zealand glow worms have modified tubules that generate light to attract prey to their sticky trap lines, which they dangle from cave ceilings. Other insects that eat toxic plants have special mechanisms to quickly excrete any toxins through the tubules.
Malpighian tubules are slender tubes with walls composed of a single layer of cells. Most are highly convoluted and bathed in hemolymph, the arthropod equivalent of blood and lymph fluid, for much of their length. They are reinforced with proteins and have structures to help push any wastes along. Most arthropods have muscles that move the tubules around, although some species lack these muscles and others lack tubules altogether.Learn more about Zoology
Animals with exoskeletons include all arthropods such as insects, crustaceans and spiders as well as many other invertebrate animals such as shelled mollusks. Shelled mollusks include snails, tusk shells, clams, nautilus and chitons. An exoskeleton is essentially an outer skeleton that protects and supports an animal's body.Full Answer >
Insects belong to the largest phylum of the animal kingdom and are called arthropods. According to the Encyclopaedia Britannica, insects are members of the Arthropoda phylum and make up 84 percent of all the known animals on Earth.Full Answer >
The common characteristics of arthropods are they are invertebrates, which means they lack backbones. In fact, they lack bones of any kind but possess a protective exoskeleton, which they molt in order to grow and repair themselves. They also have segmented bodies.Full Answer >
Like many arthropods, ticks breathe air through tiny openings along their body called "spiracles." Ticks are famous for surviving periods underwater because they have a reduced need for oxygen compared to other creatures. A tick breathes between one and 15 times an hour.Full Answer >