(n.) A conical calcareous fossil, tapering to a point at the lower extremity, with a conical cavity at the other end, where it is ordinarily broken; but when perfect it contains a small chambered cone, called the phragmocone, prolonged, on one side, into a delicate concave blade; the thunderstone. It is the internal shell of a cephalopod related to the sepia, and belonging to an extinct family. The belemnites are found in rocks of the Jurassic and Cretaceous ages.
Example Sentences:
(1) Start your exploring at Bearreraig Bay, where, if you are lucky, you may find belemnites, ammonites and bivalves.
(2) Six Holstein cows in mid-lactation were placed on a diet naturally low in 13C (-25.0% vs Pee Dee belemnite [PDB] an international carbon isotope standard), based on alfalfa-barley, and six others were placed on a diet naturally enriched in 13C (-11.5% vs PDB), based on corn.
Squid
Definition:
(n.) Any one of numerous species of ten-armed cephalopods having a long, tapered body, and a caudal fin on each side; especially, any species of Loligo, Ommastrephes, and related genera. See Calamary, Decacerata, Dibranchiata.
(n.) A fishhook with a piece of bright lead, bone, or other substance, fastened on its shank to imitate a squid.
Example Sentences:
(1) One of the most recent was in June last year, when a boatload of anglers came across a dead 23ft squid off Port Salerno on the state's Atlantic coast.
(2) To order your main course (from £7.50), squeeze through the tightly packed tables to the kitchen and select whatever catches your eye from an array of dishes that includes roast lamb, salmon with seafood risotto, stuffed cabbage, and sublime stuffed squid (£14), which comes with tomato rice studded with succulent octopus.
(3) Video-enhanced contrast light microscopy was used to directly observe dynamic length changes in native, MAP-containing microtubules from squid axoplasm.
(4) Lens crystallins were isolated from cephalopods, octopus and squid.
(5) Anion conductances of giant axons of squid, Sepioteuthis, were measured.
(6) A novel nonapeptide, sequence YAIVARPRFamide, was isolated from brain extracts of the squid, L. vulgaris.
(7) n-Aequorin J, a luminescent protein which responds to calcium concentration changes in the order of several hundred micromoles, was injected into the preterminal fiber in the squid giant synapse.
(8) The transmembrane potential of voltage-clamped squid giant axon is increased to compensate for a reduction in the rate of potassium channel kinetics when artificial seawater with trivalent erbium ion is substituted for artificial seawater.
(9) During both of them the magnetic field pattern, determined with a 7- or 24-channel SQUID magnetometer, suggested a dipolar current source.
(10) When a bright light flash is absorbed by a small region in the outer segments of squid photoreceptors fixed in glutaraldehyde, a brief pulse of membrane current flows locally.
(11) (6) It is concluded that in the squid axon the effects on inactivation are not the main reason for the reduction of the sodium current by benzocaine and that, in common with many other neutral anaesthetics, there are at least two sites at which benzocaine acts.
(12) Evoked release of transmitter at the squid giant synapse was examined under conditions where the calcium ion concentration in the presynaptic terminal was manipulated by inhibitors of calcium sequestration.
(13) We have recorded spontaneous magnetoencephalographic (MEG) activity during overnight natural sleep in 4 healthy adults with a 24-channel SQUID gradiometer, mainly over the sides of the head.
(14) Jeletzkya douglassae Johnson and Richardson is described as the oldest known representative of an extant squid group.
(15) The myosin-linked regulatory system rather than the thin-filament-linked regulatory system was predominant in squid myosin B. Squid myosin B required higher Ca2+ and Sr2+ concentrations for Mg-ATPase activity; half-maximal activation of Mg-ATPase was obtained at 0.8 micron Ca2+ and 28 micron Sr2+ with skeletal myosin B, and at 2.5 micron Ca2+ and 140 micron Sr2+ with squid myosin B.
(16) To test the hypothesis that inositol trisphosphate (InsP3) mediates adaptation and excitation in invertebrate photoreceptors, we measured its formation on a rapid time scale in squid retinas.
(17) The developments include a DC SQUID with FM read-out, resulting in the most compact SQUID electronics so far, a planar microwave biased RF SQUID with very high slew rate, and efforts to create reliable SQUIDs with sufficient sensitivity for biomagnetic applications that are cooled by liquid nitrogen.
(18) We report here that a transparent tissue, derived from muscle but functioning as a lens in the light-emitting organ of a squid, Euprymna scolopes, shows striking biochemical convergence with the epidermally derived ocular lenses of some mammals and cephalopods.
(19) (3) The two stable states of the nerve membrane, which are readily demonstrable in TEA-treated or internally perfused squid giant axons, are shown to represent bivalent cation-rich and univalent cation-rich states of the nerve membrane.
(20) Previous work has revealed that 4S RNA is the primary species of RNA in the axoplasm from the giant axons of the squid and Myxicola.