Arthropods

Animals classified as arthropods would include the scorpion, the woodlouse, the coconut crab, the mosquito, the water-flea, krill, the botfly, the giant weta, and the Japanese spider-crab.

The hexapoda subphylum containing the insecta class is the largest with around a million described arthropod species.

Crustaceans such as crabs and lobsters. Also water fleas and the other small things swimming around.

Yes indeed centipedes and millipedes are arthropods; having the classic arthropod characteristics of segmented bodies, joint appendages, and an exoskeleton. They fall under the myriapod ("many-legs") subphylum below phylum Arthropoda (a separate grouping from the insects).

Tracheal tubes

Yes, arthropods are eukaryotes, since they have cells with organized nuclei and membranous organelles (cell organs). Contrast with the much simpler prokaryotes which have no nucleus bound by membranes, and the entire organism is usually just one cell.

Arthropods molt (moult) in a process called ecdysis. It is necessary for growth because of the inflexibility of the exoskeleton. The old shell remnants are called exuviae.

Note that the term 'anthropod' should not be confused with 'arthropod'; anthropods are humans or humanoids and do not moult in the canonic sense.

Grass hoppers are classified under phylum Arthropoda (the arthropods) because they have segmented bodies, an exoskeleton made from chitin, and joint appendages, the defining characteristics of the phylum.

The arthropods are mainly classified depending upon the appendages present.

The phylum arthropoda is classified in to four subphylums

subphylum: Trilobita (Tri= three; lobita=lobe). The dorsal exoskeleton shows three lobes

subphylum: Chelicerata (Gr., chele= claw + keros=horn+ata=group)

subphylum : Myriapoda

subphylum: Hexapoda

subphylum: crustacea

Lay eggs

All arthropods apart from most insects have wings.

The lobster fits the description quite nicely of five leg pairs (order Decapoda), two antenna pairs (the biramous characteristic of crustaceans) and two body sections (cephalothorax, and abdomen or tail).

Nope, it's a mollusc, just like slugs and snails. It's in another phylum. Arthropods are insects, arachnids, crustaceans etc, with a hard exoskeleton covering their entire body and no squishy bits at all.

A sampling of ten arthropods might yield some the decapods (ten-legged crustaceans) such as the lobster, crab, shrimp, krill, crayfish, prawns; one could also appeal for examples to the relatives of the insect that stung poor Dudley Moore's character George in the movie "10" when he was trying to spy on Jenny (Bo Derek); viz, the bee, and its distant kin the Asian giant hornet or "yak killer hornet". Interestingly enough, on insect abdomens there are usually ten segments, sometimes eleven (though it may seem less because segmentation may be internal). Then there's the Japanese spider crab, one example of which was measured with a claw-span of over ten feet across; and the eurypterid, a now extinct arthropod, possibly a fossil of which was found in Cambrian strata dating back five hundred and ten million years and thought to be among the first evidence of animals on land.

Yes, all arthropods are creatures.

Any of numerous invertebrate animals of the phylum Arthropoda, including the insects, crustaceans, arachnids, and myriapods, that are characterized by a chitinous exoskeleton and a segmented body to which jointed appendages are articulated in pairs.

Yes, arthropods have to moult in order to increase in size, because their exoskeleton is rigid and inhibits growth. The process is called ecdysis and is not limited only to arthropods; it is a characteristic of their clade, ecdysozoa, which includes nematodes and other phyla.

The external covering on arthropods is called the exoskeleton (or cuticle). It is made of a tough protein called chitin, a long chain polymer comparable to cellulose. Because it's inflexible, arthropods need to shed it (moult) in order to grow.

If you mean by number of species and/or total actual organisms, yes. By the way, if you didn't know, arthropod means "jointed foot", and it is the group of animals with exoskeletons; i.e. insects; arachnids--ticks, spiders, mites, scorpions, whipscorpions, harvestmen; crustaceans--crabs, lobsters, shrimp, isopods (roly-polies, sow bugs, pill bugs, wood lice); and the 'pedes--millipedes and centipedes.

Arthropods and sponges are two major divisions in taxonomy called Phyla (singular, phylum). Phylum Arthropoda ("joint appendages"), or the arthropods, includes such creatures as insects, spiders, millipedes, crustaceans, etc. Phylum Porifera ("pore-bearing") are the sponges.

No they are not, they just speed up the decomposers work of ridding the world of dead plants and animals they should slow down decomposition

The primary decomposers are Bacteria and Fungi

exoskeleton
Arthropods have a skeleton on the outside, called an exoskeleton. (By contrast, vertebrates will have an internal skeleton or endoskeleton). The exoskeleton of arthropoda is made of a tough protein called chitin, a long chain polymer comparable to cellulose. It fills the same role as the protein keratin in other animals where it would be found in hair, nails, hooves, claws, beaks, etc. Some arthropods, like crustaceans, further harden their chitin exoskeleton by biomineralization with calcium carbonate. Because it is inflexible, the organism has to periodically shed it (moult) in order to grow, a process called ecdysis.

head, thorax, and abdomen

The Arachnid class of arthropods under subphylum Chelicerata have only two major body sections (tagmata) called the cephalothorax and abdomen; they also usually have eight legs as adults, and no wings nor antennae.