What's the difference between cretaceous and period?

Cretaceous


Definition:

  • (a.) Having the qualities of chalk; abounding with chalk; chalky; as, cretaceous rocks and formations. See Chalk.

Example Sentences:

  • (1) In the investigation, the arcade-shaped prisms typical of recent mammals were first seen in material from the Cretaceous period.
  • (2) Fossil glycoproteins of the soluble organic matrix are present in an 80-million-year-old mollusk shell from the Late Cretaceous Period.
  • (3) The Masiakasaurus knopfleri, a theropod dinosaur from the Late Cretaceous period, was named after him in 2001.
  • (4) Species of Spirorchis arose and diversified with North America emydids following the separation of North America and Europe in the late Cretaceous or early Tertiary periods.
  • (5) The diversity of tetrapods increased from the Devonian to the Permian, remained roughly constant during the Mesozoic, and then began to increase in the late Cretaceous, and continued to do so during the Tertiary.
  • (6) We report here the discovery of two mammal teeth from the early Cretaceous of Cameroon.
  • (7) Consequently, the brain's geometry has changed notably since the late Cretaceous.
  • (8) The known range of the Primates is extended down from the middle Paleocene to the early Paleocene and late Cretaceous by a new genus and two new species from Montana, Purgatorius unio and P. ceratops.
  • (9) In the Late Cretaceous (80 to 65 million years ago) when the fossil record improves, mammalian enamel investigated from North American localities, are found to be prismatic; allotherian (multituberculate) and metatherian (marsupial) enamels are usually tubular, while eutherian (placental) ones are not.
  • (10) Spirorchinae arose later (late Cretaceous period) as a Laurasian component parasitic in the more recent pond turtles (Emydidae + Bataguridae).
  • (11) Dr Corwin Sullivan of the Institute of Palaeontology and Palaeoanthropology states that “It’s always great to meet a new Cretaceous tyrant, and Lythronax might just be a particularly noteworthy one.
  • (12) Dr Lee Margetts, another member of the Manchester team, said: "The new study clearly demonstrates the dinosaur was more than capable of strolling across the Cretaceous planes of what is now Patagonia, South America."
  • (13) Integral to the origin of the eutherian style of embryogenesis was the evolution during Cretaceous time of neomorphic, extraembryonic tissues (i.e., trophoblast) having physiological properties that allowed the unique combination of intimate apposition of fetal and maternal tissues and circulatory systems, along with sustained, active morphogenesis.
  • (14) If so, these pathways are as old in phylogenetic history as the last common ancestor of marsupial and placental mammals--dating from the late Jurassic to early Cretaceous, perhaps 145-120 million years ago.
  • (15) Levels of sequence divergence, as well as the age and affinities of some mainland fossil taxa, suggest that the origin of Cricosaura was associated with the tectonic evolution of the Greater Antilles in the late Cretaceous.
  • (16) – Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian, Triassic, Jurassic, Cretaceous … 'What will survive of us is love', wrote Philip Larkin.
  • (17) These changes suggest: (i): an expansion in the exploitation of dry fruits and seeds by mammals on the ground as well as in the trees after the terminal Cretaceous dinosaur extinction; (ii) a relation between large nuts and rodents, which appear in the late Palaeocene and radiate in the late Eocene; (iii) a relation between primates and fleshy fruits established in the early-Middle Eocene when tropical forests reached their maximum latitudinal extent; (iv) a hiatus of several million years in the vertebrate exploitation of leaves after dinosaur extinction and before the first few mammalian herbivores in the Middle Palaeocene, followed by an expansion in the late Eocene when climates cooled and more open vegetation became established.
  • (18) Photograph: Andy Farke In the Late Cretaceous of North America, hadrosaurs were at their peak.
  • (19) Like these giants from the end of the Cretaceous, Lythronax has a relatively broad skull with the orbits facing forwards.
  • (20) These showed that the amphiumid and dicamptodontine-rhyacotritonine nerve patterns had evolved by the Late Cretaceous, and the sirenid pattern had probably evolved by that time.

Period


Definition:

  • (n.) A portion of time as limited and determined by some recurring phenomenon, as by the completion of a revolution of one of the heavenly bodies; a division of time, as a series of years, months, or days, in which something is completed, and ready to recommence and go on in the same order; as, the period of the sun, or the earth, or a comet.
  • (n.) A stated and recurring interval of time; more generally, an interval of time specified or left indefinite; a certain series of years, months, days, or the like; a time; a cycle; an age; an epoch; as, the period of the Roman republic.
  • (n.) One of the great divisions of geological time; as, the Tertiary period; the Glacial period. See the Chart of Geology.
  • (n.) The termination or completion of a revolution, cycle, series of events, single event, or act; hence, a limit; a bound; an end; a conclusion.
  • (n.) A complete sentence, from one full stop to another; esp., a well-proportioned, harmonious sentence.
  • (n.) The punctuation point [.] that marks the end of a complete sentence, or of an abbreviated word.
  • (n.) One of several similar sets of figures or terms usually marked by points or commas placed at regular intervals, as in numeration, in the extraction of roots, and in circulating decimals.
  • (n.) The time of the exacerbation and remission of a disease, or of the paroxysm and intermission.
  • (n.) A complete musical sentence.
  • (v. t.) To put an end to.
  • (v. i.) To come to a period; to conclude. [Obs.] "You may period upon this, that," etc.

Example Sentences:

  • (1) Without medication atypical ventricular tachycardia develops, in the author's opinion, most probably when bradycardia has persisted for a prolonged period.
  • (2) Disease stabilisation was associated with prolonged periods of comparatively high plasma levels of drug, which appeared to be determined primarily by reduced drug clearance.
  • (3) Although the mean values for all hemodynamic variables between the two placebo periods were minimally changed, the differences in individual patients were striking.
  • (4) It was shown in experiments on four dogs by the conditioned method that the period of recovery of conditioned activity after one hour ether anaesthesia tested 7 to 7.5 days.
  • (5) Under blood preservation conditions the difference of the rates of ATP-production and -consumption is the most important factor for a high ATP-level over long periods.
  • (6) No significant change occurred in the bacterial population of our hospital unit during the period of the study (more than 3 years).
  • (7) The secondary leukemia that occurred in these patients could be distinguished from the secondary leukemia that occurs after treatment with alkylating agents by the following: a shorter latency period; a predominance of monocytic or myelomonocytic features; and frequent cytogenetic abnormalities involving 11q23.
  • (8) Sixteen patients in whom schizophrenia was initially diagnosed and who were treated with fluphenazine enanthate or decanoate developed severe depression for a short period after the injection.
  • (9) During the study period four family outbreaks and seven recurrences of infection were observed.
  • (10) After a period on fat-rich diet the patient's physical fitness was increased and the recovery period after the acute load was shorter.
  • (11) During this period he developed autoimmune haemolytic anaemia, a rare complication of myelofibrosis.
  • (12) Pituitary weight, mitotic index and chromosomes were studied in male rats following a single or repeated dose of estradiol-benzoate for a total period of 210 days.
  • (13) Most thyroid hormone actions, however, appear in the perinatal period, and infants with thyroid agenesis appear normal at birth and develop normally with prompt neonatal diagnosis and treatment.
  • (14) Maximal aberration yields were observed for 2,4-diaminotoluene, 2,6-diaminotoluene and cytosine beta-D-arabinofuranoside from 17 to 21 h, eugenol from 15 to 21 h, cadmium sulfate from 15 to 24 h and 2-aminobiphenyl, from 17 to 24 h. For adriamycin at 1 microM, the % aberrant cells remained elevated throughout the period from 9 to 29 h, while small increases at 0.1 microM ADR were found only at 13 and at 25 h. For most chemicals the maximal aberration yield occurred at a different time for each concentration tested.
  • (15) Accuracy of discrimination of letters at various preselected distances was determined each session while Ortho-rater examinations were given periodically throughout training.
  • (16) During electrophysiologic study, the effect of propafenone on the effective refractory period of the accessory pathway was determined, as well as its effect during orthodromic atrioventricular (AV) reentrant tachycardia and atrial fibrillation.
  • (17) Time-series analysis and multiple-regression modeling procedures were used to characterize changes in the overall incidence rate over the study period and to describe the contribution of additional measures to the dynamics of the incidence rates.
  • (18) Throughout the period of rehabilitation, the frequent changes of a patient's condition may require a process of ongoing evaluation and appropriate adjustments in the physical therapy program.
  • (19) Anthropometric and nutritional (serum albumin and transferrin) values were normal in both groups both at the beginning and at the end of the treatment period.
  • (20) Analysis of conjugated discharges ACHs showed that they appeared predominantly periodically (87% of cases).