( ( ( An ( early ( or ( primary oocyte ) ) ) ) ( -LRB- ( ( primordial follicle ) -RRB- ) ) ) ( ( is ( surrounded ( by ( ( a ( single layer ) ) ( of ( ( granulosa cells ) ( ( separated ( by ( a ( basement membrane ) ) ) ) ( from ( Thecal cells ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT An) (JJ early) (CC or) (JJ primary) (NN oocyte)) (PRN (-LRB- -LRB-) (NP (JJ primordial) (NN follicle)) (-RRB- -RRB-))) (VP (VBZ is) (VP (VBN surrounded) (PP (IN by) (NP (NP (DT a) (JJ single) (NN layer)) (PP (IN of) (NP (NP (NN granulosa) (NNS cells)) (VP (VBN separated) (PP (IN by) (NP (DT a) (NN basement) (NN membrane))) (PP (IN from) (NP (NNP Thecal) (NNS cells)))))))))) (. .)))
An early or primary oocyte ( primordial follicle) is surrounded by a single layer of granulosa cells separated by a basement membrane from Thecal cells.
(ROOT (S (NP (JJ Biological) (NNS membranes)) (VP (VP (VBP surround) (NP (NNS cells))) (CC and) (VP (VBP serve) (S (VP (TO to) (VP (VB keep) (NP (NP (DT the) (NNS insides)) (VP (VBN separated) (PP (IN from) (NP (DT the) (NNS outsides)))))))))) (. .)))