exoskeleton

Examples of exoskeleton in the following topics:

• Types of Skeletal Systems

  • An exoskeleton is an external, hard, encasement on the surface of an organism.
  • For example, the shells of crabs and insects are exoskeletons .
  • As with vertebrates, muscles must cross a joint inside the exoskeleton.
  • Shortening of the muscle changes the relationship of the two segments of the exoskeleton.
  • Because the exoskeleton is acellular and does not grow as the organism grows, arthropods must periodically shed their exoskeletons.

• Limits on Animal Size and Shape

  • Animal shape and body size are influenced by environmental factors as well as the presence of an exoskeleton or an endoskeleton.
  • Most animals have an exoskeleton, including insects, spiders, scorpions, horseshoe crabs, centipedes, and crustaceans.
  • Ingrowths of the exoskeleton called apodemes function as attachment sites for muscles, similar to tendons in more advanced animals .
  • The thickness of the exoskeleton must be increased significantly to accommodate any increase in weight.
  • Apodemes are ingrowths on arthropod exoskeletons to which muscles attach.

• Phylum Arthropoda

  • Arthropods are the largest grouping of animals all of which have jointed legs and an exoskeleton made of chitin.
  • Arthropods also show the presence of an exoskeleton made principally of chitin, which is a waterproof, tough polysaccharide.
  • In order to grow, the arthropod must shed the exoskeleton during a process called ecdysis ("to strip off"); this is a cumbersome method of growth.

• Superphylum Ecdysozoa

  • The most distinguishing and prominent feature of Ecdysozoans is their cuticle: a tough, but flexible exoskeleton that protects these animals from water loss, predators, and other aspects of the external environment.

• Carbohydrate Molecules

  • Arthropods have an outer skeleton, the exoskeleton, which protects their internal body parts.
  • This exoskeleton is made of chitin, which is a polysaccharide-containing nitrogen.

• Phylum Nematoda

  • The name derives from the word ecdysis, which refers to the shedding, or molting, of the exoskeleton.
  • They possess an exoskeleton that prevents them from drying out .

• Subphyla of Arthropoda

  • Crustaceans have a chitinous exoskeleton that is shed by molting whenever the animal increases in size.
  • The exoskeletons of many species are also infused with calcium carbonate, which makes them even stronger than in other arthropods.

• The Fossil Record as Evidence for Evolution

  • Fossils usually consist of the portion of the organisms that was partially mineralized during life, such as the bones and teeth of vertebrates or the chitinous or calcareous exoskeletons of invertebrates.

• The Alkaline Earth Metals

  • Strontium plays an important role in marine aquatic life, especially hard corals, which use strontium to build their exoskeletons.

• Marine Biomes

  • The exoskeletons of shoreline crustaceans are tough, protecting them from desiccation and wave damage.