( ( In animals ) ( , ( ( the ( plasma membrane ) ) ( ( ( ( is ( ( the ( outer boundary ) ) ( of ( the cell ) ) ) ) , ) ( while ( ( in ( ( plants and ) prokaryotes ) ) ( it ( ( is usually ) ( covered ( by ( a ( cell wall ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NNS animals))) (, ,) (NP (DT the) (NN plasma) (NN membrane)) (VP (VBZ is) (NP (NP (DT the) (JJ outer) (NN boundary)) (PP (IN of) (NP (DT the) (NN cell)))) (, ,) (SBAR (IN while) (S (PP (IN in) (NP (NNS plants) (CC and) (NNS prokaryotes))) (NP (PRP it)) (VP (VBZ is) (ADVP (RB usually)) (VP (VBN covered) (PP (IN by) (NP (DT a) (NN cell) (NN wall)))))))) (. .)))
In animals, the plasma membrane is the outer boundary of the cell, while in plants and prokaryotes it is usually covered by a cell wall.
(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))))) (. .)))