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A dragonfly in its radical final moult, metamorphosing from an aquatic nymph to a winged adult.. In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is a process by which an animal casts off parts of its body to serve some beneficial purpose, either at specific times of the year, or at specific points in ...
Birds cannot use their beaks to apply preen oil to their own heads. Instead, many use their feet in an action called scratch-preening. Once they have gathered preen oil on their beak, they scrape a foot across their bill to transfer the oil, and then scratch the oil into the feathers on their head. [28] Longer-necked birds may rub their head ...
Their cuticles vary in the details of their structure, but generally consist of three main layers: the epicuticle, a thin outer waxy coat that moisture-proofs the other layers and gives them some protection; the exocuticle, which consists of chitin and chemically hardened proteins; and the endocuticle, which consists of chitin and unhardened ...
[6] [7] [8] Quizlet's blog, written mostly by Andrew in the earlier days of the company, claims it had reached 50,000 registered users in 252 days online. [9] In the following two years, Quizlet reached its 1,000,000th registered user. [10] Until 2011, Quizlet shared staff and financial resources with the Collectors Weekly website. [11]
Since the cuticle of these animals typically forms a largely inelastic exoskeleton, it is shed during growth and a new, larger covering is formed. [1] The remnants of the old, empty exoskeleton are called exuviae. [2] After moulting, an arthropod is described as teneral, a callow; it is "fresh", pale and soft-bodied.
Prior to the onset of the first meraspid stage the animal had a two-part structure—the head and the plate of fused trunk segments, the pygidium. During the meraspid stages, new segments appeared near the rear of the pygidium as well as additional articulations developing at the front of the pygidium, releasing freely articulating segments ...
A lobster is heavily cephalized, with eyes, antennae, multiple mouthparts, and the brain (inside the armoured exoskeleton), all concentrated at the animal's head end. Cephalization is an evolutionary trend in animals that, over a sufficient number of generations, concentrates the special sense organs and nerve ganglia towards the front of the ...
In many cases the cast skin peels backward over the body from head to tail, in one piece like an old sock. A new, larger, and brighter layer of skin has formed underneath. [5] [7] An older snake may shed its skin only once or twice a year, but a younger snake that is still growing may shed up to four times a year. [7]