What's the difference between necessary and obligatory?

Necessary


Definition:

  • (a.) Such as must be; impossible to be otherwise; not to be avoided; inevitable.
  • (a.) Impossible to be otherwise, or to be dispensed with, without preventing the attainment of a desired result; indispensable; requiste; essential.
  • (a.) Acting from necessity or compulsion; involuntary; -- opposed to free; as, whether man is a necessary or a free agent is a question much discussed.
  • (n.) A thing that is necessary or indispensable to some purpose; something that one can not do without; a requisite; an essential; -- used chiefly in the plural; as, the necessaries of life.
  • (n.) A privy; a water-closet.
  • (n.) Such things, in respect to infants, lunatics, and married women, as are requisite for support suitable to station.

Example Sentences:

  • (1) Apparently, the irradiation with visible light of a low intensity creates an additional proton gradient and thus stimulates a new replication and division cycle in the population of cells whose membranes do not have delta pH necessary for the initiation of these processes.
  • (2) The low affinity of several N1-alkylpyrroleethylamines suggests that the benzene portion of the alpha-methyltryptamines is necessary for significant affinity.
  • (3) Intravesical BCG is clearly superior to oral BCG, and controlled studies have demonstrated that percutaneous administration is not necessary.
  • (4) These studies show that metabolic activation is necessary for the expression of the mutagenic activity of aflatoxins B1 and G1 in N. crassa.
  • (5) In practice, however, the necessary dosage is difficult to predict.
  • (6) In order to control noise- and vibration-caused diseases it was necessary not only to improve machines' quality and service conditions but also to pay special attention to the choice of operators and to the quality of monitoring their adaptation process.
  • (7) It is likely that trunk mobility is necessary to maintain integrity of SI joint and that absence of such mobility compromises SI joint structure in many paraplegics.
  • (8) If there is a will to use primary Care centres for effective preventive action in the population as a whole, motivation of the professionals involved and organisational changes will be necessary so as not to perpetuate the law of inverse care.
  • (9) Obamacare price hikes show that now is the time to be bold | Celine Gounder Read more No longer able to keep patients off their plans outright, insurers have resorted to other ways to discriminate and avoid paying for necessary treatments.
  • (10) Duesberg contends that HIV is neither necessary nor sufficient to cause AIDS.
  • (11) It is therefore necessary, to look at typical clinical manifestations, i.e.
  • (12) We have examined the in vitro membrane assembly characteristics of a variety of leader peptidase mutants and found that domains required for insertion in vivo are also necessary for insertion in vitro.
  • (13) Two hours after the administration, the combinations of ethanol plus diazepam and ethanol plus meclophenoxate impaired significantly the number of necessary repetitions.
  • (14) The first experiment gave good results, although only one participant had any previous experience of hinge axis location, and it is debatable whether or not this experience is necessary before satisfactory results can be obtained.
  • (15) For consistent identification of the normal pancreas, preliminary longitudinal scanning at, or near, the mid-line and subsequent oblique scanning in the long axis are necessary prerequisites in delineating the anatomic outline of the pancreas.
  • (16) Survival and healing of "extremely severe" grade intoxication can only be obtained through a surgical intervention within the first hours; a laparotomy will indicate the depth of the lesions, which is not determined by endoscopy, and will consist of Celerier's stripping method and if necessary a gastrectomy, more seldom a cephalic duodeno-pancreatectomy.
  • (17) Socio-economic improvement or behavioural changes appear necessary for the control of trachoma in endemic areas.
  • (18) This stimulation is mediated by one receptor with an apparent affinity of 3.3 X 10(-6) M. The hydroxyl group in the para position on phenylethanolamine was absolutely necessary to obtain an agonist whereas the meta hydroxyl group or the presence of a catechol almost suppressed the activity.
  • (19) Provided that adequate reflection is given and the appropriate moment chosen, it is well tolerated and provides all the necessary information.
  • (20) Total excisional biopsy is necessary to properly assess an adenoma microscopically.

Obligatory


Definition:

  • (a.) Binding in law or conscience; imposing duty or obligation; requiring performance or forbearance of some act; -- often followed by on or upon; as, obedience is obligatory on a soldier.

Example Sentences:

  • (1) It is important to note that the proposed mechanism is not obligatory for androgen or other steroid hormone action.
  • (2) However, besides these obligatory alterations a high inter- and intraindividual variability of structural aspects is found in MS lesions.
  • (3) The presence of the other islet cell-types may be obligatory for these appropriate responses.
  • (4) From the derived cell flux in these compartments we suggest that 1) many more pre-B cells are produced than needed by the peripheral B cell pool; 2) if TdT is an obligatory stage in B cell genesis, there must be at least two cell cycles in the pre-B cell compartment; 3) if it is not, the TdT+ stage may be bypassed, with HIS24+TdT-Ig- cells perhaps feeding directly into the pre-B cell compartment.
  • (5) Neither cytochrome a nor cytochrome c appears to be an obligatory intermediate in cyanide-sensitive nicotinamide adenine dinucleotide oxidation in B. subtilis.
  • (6) Thus, the results of this study indicate that retinal is an obligatory intermediate in the hepatic production of retinoic acid from retinol and that cytosolic and microsomal retinol dehydrogenases play a key role in this process.
  • (7) Thus, even though LPS is a potent inducer of IFN-beta in murine macrophages, class I IFN expression may not be an obligatory intermediate event in the LPS-driven activation of ISRE binding activity.
  • (8) The four hosts (Mollusc -- Crustacean -- Odonat -- Amphibian) are obligatory in the life cycle for it is impossible to infect the Insects directly with the cecariae or the frog (tadpoles as well as adults) with the mesocercariae.
  • (9) The synergistic actions of E2 and either AA, the obligatory precursor of PGF2 alpha, or A23187, an enhancer of AA release from phospholipid stores, point to a stimulatory effect of E2 on prostaglandin synthase activity.
  • (10) No wt-1 expression was detected at any stage of tooth development showing that wt-1 is not obligatory for regulation of Egr-1 expression.
  • (11) These findings show that class switch by deletion of DNA regions in mature plasma cells is not obligatory for the secretion of immunoglobulin classes other than IgM.
  • (12) Serotonin plays an obligatory role in the initiation and expression of leech feeding behavior by its differential modulation of central neuronal networks and peripheral glands and muscles.
  • (13) However, in spite of these similarities, they differentially stimulate estrogenic responses that were previously thought to be interrelated and obligatory for full estrogenic action.
  • (14) These results, together with data from the native proteins, are consistent with obligatory 1-electron transfer between dehydrogenase and ETF possibly involving the exposed dimethylbenzene edge of ETF.
  • (15) Although Mg2+ is absolutely required for activation of adenylate cyclase by the GTP analogue guanosine 5'-[beta gamma-imido]triphosphate (p[NH]ppG), it is not obligatory for p[NH]ppG-stimulated ADP-ribosylation by cholera toxin.
  • (16) This suggests that normally the midline floor plate cells do provide guidance cues, but that these cues are not obligatory.
  • (17) The protein supply recommended for a certain age group should not be obligatory for the individual child.
  • (18) The results strongly suggest that the obligatory antigen processing event required for helper T cell recognition of alloantigen is simply the insertion of the alloantigen into the same membrane bilayer as the syngeneic Ia restricting element.
  • (19) This new function is derived by assuming that all chromosome arms except the short arms of acrocentric chromosomes hav an obligatory chiasma, and that the remaining chiasmata are distributed at random; assumptions which may correspond reasonably well to reality.
  • (20) Its somewhat unique features have attracted widespread interest both nationally and internationally and may be seen as part of an international movement towards obligatory CME in Western Medicine.