( ( Many prokaryotes ) ( ( ( have ( ( ( ( an ( extra layer ) ) , ) ( called ( a capsule ) ) ) , ) ) ( outside ( the ( cell wall ) ) ) ) . ) )
(ROOT (S (NP (JJ Many) (NNS prokaryotes)) (VP (VBP have) (NP (NP (DT an) (JJ extra) (NN layer)) (, ,) (VP (VBN called) (NP (DT a) (NN capsule))) (, ,)) (PP (IN outside) (NP (DT the) (NN cell) (NN wall)))) (. .)))
Many prokaryotes have an extra layer, called a capsule, outside the cell wall.
(ROOT (S (NP (DT The) (NN capsule)) (VP (VBZ is) (NP (NP (DT the) (NN layer)) (PP (IN outside) (NP (NP (DT the) (NN cell) (NN wall)) (PP (IN in) (NP (DT a) (NN prokaryote))))))) (. .)))
The capsule is the layer outside the cell wall in a prokaryote.