细菌生长繁殖的规律王利沙Thelawsofbacterialgrowthandreproducti.pptx

细菌生长繁殖的规律主讲老师：王利沙ThelawsofbacterialgrowthandreproductionWeifangNursingVocationalCollege潍坊护理职业学院

细菌个体的生长繁殖规律Thegrowthandreproductionpatternsofindividualbacteria二分裂：核质DNA复制，细胞成分增加，胞体增大，细胞开始分裂。Twosplits:NuclearcytoplasmicDNAreplicationleadstoanincreaseincellularcomponents,enlargementofthecellbody,andinitiationofcelldivision.核质DNANucleocytoplasmicDNADNA复制DNAreplication细胞伸长Cellelongation形成隔膜Formadiaphragm分裂成两个子细胞Splitintotwodaughtercells

代时：细菌分裂倍增的时间。Generationtime:thetimewhenbacteriadivideandmultiply.

将一定数量的细菌接种于适宜的液体培养基中培养，间隔一定时间取样检测活菌数，绘制细菌的生长曲线。Inoculateacertainnumberofbacteriaintoasuitableliquidculturemediumforcultivation,takesamplesatregularintervalstodetectthenumberofviablebacteria,andplotthegrowthcurveofthebacteria.

迟缓期Delayedperiod细菌不分裂，菌数不增加，代谢活跃为细菌的分裂做准备。Bacteriadonotdivide,thenumberofbacteriadoesnotincrease,andmetabolicactivitypreparesforbacterialdivision.对数期Logarithmicperiod细菌生长繁殖迅速，形态、染色性、生物活性都很典型。Bacteriagrowandreproducerapidly,withtypicalmorphology,staining,andbiologicalactivity.

稳定期Stableperiod细菌繁殖速度下降，繁殖数和死亡数趋于平衡，产生芽胞和代谢产物。Thespeedofbacterialreproductiondecreases,andthenumberofreproductionanddeathtendstobalance,producingsporesandmetabolites.衰退期Declineperiod细菌繁殖速度变慢，死亡数繁殖数，菌体畸变。Thespeedofbacterialreproductionslowsdown,thenumberofdeathsexceedsthenumberofreproduction,andthebacterialcellsbecomedistorted.

观察细菌的形态、代谢、遗传性状和测定药物或环境因素对细菌的影响，宜采用对数生长末期的细菌；Observingthemorphology,metabolism,genetictraitsofbacteriaanddeterminingtheeffectsofdrugsorenvironmentalfactorsonbacteria,itisadvisabletousebacteriaattheendoflogarithmicgrowth.计数细菌的最大生长量，应采用稳定期的培养物。Themaximumgrowthrateofbacteriashouldbecountedusingstableculture.研究意义Researchmeaning

细菌生长曲线只有在体外人工培养的条件下才能观察到。Thebacterialgrowthcurvecanonlybeobservedunde