( ( ( Cholesterol ( although ( absent ( in ( plasma membranes ) ) ) ) ) ( from ( ( ( most ( plant cells ) ) and ) bacteria ) ) ) ( , ( ( ( ( constitutes up ) ( to ( ( 50 % ) ( of ( the lipid ) ) ) ) ) ( molecules ( in ( ( the ( plasma membrane ) ) ( of ( certain ( animal cells ) ) ) ) ) ) ) . ) ) )
(ROOT (SINV (S (VP (VB Cholesterol) (ADJP (IN although) (JJ absent) (PP (IN in) (NP (NN plasma) (NNS membranes)))) (PP (IN from) (NP (NP (JJS most) (NN plant) (NNS cells)) (CC and) (NP (NNS bacteria)))))) (, ,) (VP (VBZ constitutes) (PRT (RP up)) (PP (TO to) (NP (NP (CD 50) (NN %)) (PP (IN of) (NP (DT the) (NN lipid)))))) (NP (NP (NNS molecules)) (PP (IN in) (NP (NP (DT the) (NN plasma) (NN membrane)) (PP (IN of) (NP (JJ certain) (NN animal) (NNS cells)))))) (. .)))
Cholesterol although absent in plasma membranes from most plant cells and bacteria, constitutes up to 50% of the lipid molecules in the plasma membrane of certain animal cells.
(ROOT (S (NP (DT A) (NN plasma) (NN membrane)) (VP (VBZ encloses) (NP (NP (DT the) (NN border)) (PP (IN of) (NP (NN animal) (NNS cells))))) (. .)))