TritionalshiftsofEscherichiacoliB/rtorichermediahavebeenanalyzedinsynchronouslygrowingandexponential-phasepopulations.Earlyperturbationsinthetimingofcelldivisionwereobserved.Attheslowgrowth,divisionpro-gressedatarateequaltoorlessthanthepreshiftrateforabout1h.Atintermediategrowth,bothdelaysandaccelerationindivisionwereobserved.Theextentoftheperturbationdependedupontheageofthecellsatthetimeoftheshiftandthecompositionofthepreshiftandpostshiftmedia.TheperturbationwasdifferentinthetwosubstrainsofE.coliB/r I got this from http://jb.asm.org/content/136/2/631.full.pdf hopefully it helps you
polarity of a molecule deals with the presence of net charges and partial charges. this has nothing to do with its symmetry which is determined by the molecule's structure
