atory ▁The ▁thro at - clear ▁may ▁be ▁art ic ulated ▁cons ci ously ▁or ▁un cons ci ously ▁as ▁a ▁sympt om ▁of ▁a ▁number ▁of ▁l ary ng oph ary n ge al ▁( upper ▁resp ir atory ▁tract ) ▁a il ments . ▁ ▁Vo ice ▁ ▁Cont in ual ▁thro at - clear ing ▁is ▁a ▁sympt om ▁of ▁chron ically ▁dry ▁vocal ▁c ords , ▁caused ▁by ▁ins u fficient ly ▁produced ▁amounts ▁of ▁m uc us ▁due ▁to ▁in ade qu ate ▁amounts ▁of ▁water ▁and ▁by ▁excess ive ▁amounts ▁of ▁c aff e ine ▁and ▁alco hol . ▁ ▁References ▁ ▁Category : C ough ▁Category : Gest ures <0x0A> </s> ▁N ass ell aria ▁is ▁an ▁order ▁of ▁Rh iz aria ▁belonging ▁to ▁the ▁class ▁Rad i ol aria . ▁The ▁organ isms ▁of ▁this ▁order ▁are ▁character ized ▁by ▁a ▁ske leton ▁cross ▁link ▁with ▁a ▁cone ▁or ▁ring . ▁ ▁Introduction ▁ ▁N ass ell aria ▁is ▁an ▁order ▁of ▁Rad i ol aria ▁under ▁the ▁class ▁Pol yc yst ina . ▁These ▁organ isms ▁are ▁un ic ell ular ▁e uk ary otic ▁heter ot roph ic ▁pl ank ton ▁typically ▁with ▁a ▁sil ice ous ▁cone - sh aped ▁ske leton . ▁The ▁most ▁common ▁group ▁of ▁radi ol ari ans ▁are ▁the ▁pol yc yst ine ▁radi ol ari ans , ▁which ▁are ▁divided ▁into ▁two ▁sub groups : ▁the ▁sp um ell ari ans ▁and ▁the ▁n ass ell