. e . ▁a ▁vis c ous ▁flow ). ▁Long - term ▁cre ep ▁experiments ▁( ~ 1 0 ▁years ) ▁indicate ▁that ▁the ▁vis cos ity ▁of ▁gran ite ▁and ▁glass ▁under ▁ambient ▁conditions ▁are ▁on ▁the ▁order ▁of ▁ 1 0 2 0 ▁po ises . ▁ ▁Phys i ology ▁▁ ▁Phys i ology ▁includes ▁the ▁study ▁of ▁many ▁bod ily ▁flu ids ▁that ▁have ▁complex ▁structure ▁and ▁composition , ▁and ▁thus ▁exhib it ▁a ▁wide ▁range ▁of ▁vis co el astic ▁flow ▁characteristics . ▁ ▁In ▁particular ▁there ▁is ▁a ▁special ist ▁study ▁of ▁blood ▁flow ▁called ▁hem or he ology . ▁This ▁is ▁the ▁study ▁of ▁flow ▁properties ▁of ▁blood ▁and ▁its ▁elements ▁( pl asma ▁and ▁formed ▁elements , ▁including ▁red ▁blood ▁cells , ▁white ▁blood ▁cells ▁and ▁plate lets ). ▁Blood ▁vis cos ity ▁is ▁determined ▁by ▁pl asma ▁vis cos ity , ▁h emat oc rit ▁( volume ▁fraction ▁of ▁red ▁blood ▁cell , ▁which ▁const itute ▁ 9 9 . 9 % ▁of ▁the ▁cell ular ▁elements ) ▁and ▁mechanical ▁behaviour ▁of ▁red ▁blood ▁cells . ▁Therefore , ▁red ▁blood ▁cell ▁mechan ics ▁is ▁the ▁major ▁determin ant ▁of ▁flow ▁properties ▁of ▁blood . ▁ ▁Food ▁r he ology ▁▁ ▁Food ▁r he ology ▁is ▁important ▁in ▁the ▁manufact ure ▁and ▁processing ▁of ▁food ▁products , ▁such ▁as ▁che ese ▁and ▁gel ato . ▁ ▁Th ick ening ▁agents , ▁or ▁thick en ers , ▁are ▁subst ances ▁which , ▁when ▁added ▁to ▁an ▁a