Webbclam·shell (klăm′shĕl′) n. 1. The shell of a clam. 2. Any of various devices that consist of two parts attached by a hinge and that open and close like a clamshell, especially a digging or dredging machine with a bucket that has hinged jaws or a handheld electronic device. American Heritage® Dictionary of the English Language, Fifth Edition ... Webb15 juni 2012 · Lampreys and hagfish, which together are known as the cyclostomes or ‘agnathans’, are the only surviving lineages of jawless fish. They diverged early in vertebrate evolution, before the origin of the hinged jaws that are characteristic of gnathostome (jawed) vertebrates and before the evolution of paired appendages. …
Jaw Definition & Meaning - Merriam-Webster
WebbBroken or dislocated jaw. A broken jaw is a break (fracture) in the jaw bone. A dislocated jaw means the lower part of the jaw has moved out of its normal position at one or both … Webb13 feb. 2024 · Jawless fish are very primitive fish that tend to scavenge or live as parasites. The lack of an upper and lower hinged jaw means they are only able to suck or rasp … effect hypertension
Mosasaurus hoffmannii v Pliosaurus funkei - Carnivora
WebbRealDoll's hinged jaw can open and closes as human jaws and can be adjusted to fit any body shape. The mouth cavity has also been designed to be ribbed for more pleasure. … WebbNow, hinged jaw means that there are two parts to the jaw connected with a hinge. Now, most vertebrates have hinged drawls, but not all of them. There are various fishes that … WebbIn fact, one of the most significant developments in early vertebrate evolution was the development of the jaw: a hinged structure attached to the cranium that allows an animal to grasp and tear its food. Jaws were probably derived from the first pair of gill arches supporting the gills of jawless fishes. Figure 1. effectieve spanning