C.setacomfortablehomeforherfamilyD.absorbherfamily’s stress

27.Whatistheauthor’sattitudetowardhousewives?

A.SupportiveB.DoubtfulC.OpposedD. Disappointed
C

ResearchersatUniversityofCaliforniareportthatelderlywomenwhosit formorethan10hoursadaywithlowphysicalactivityhavecellsthatare biologicallyolderbyeightyearscomparedtowomenwhoarelesssedentary.

Thestudy,publishedonlineJanuary18intheAmericanJournalof Epidemiology,foundelderlywomenwithlessthan40minutesof moderate-to-vigorousphysicalactivityperdayandwhoremainseatedformore than10hoursperdayhaveshortertelomeres（染色体终端）,whichprotect chromosomes(染色体)frombecomingbadandprogressivelyshortenwithage.

Asacellages,itstelomeresnaturallyshorten,buthealthandlifestyle factors,suchasobesityandsmoking,mayquickenthatprocess.Shortened telomeresareassociatedwithcardiovasculardisease,diabetesandmajor cancers.

“Ourstudyfoundcellsagefasterwithasedentarylifestyle. Chronological(编年的)agedoesn’talwaysmatchbiologicalage,”saidShadyab,PhD, leadauthorofthestudy.