( ( The epidermis ) ( ( has ( ( tiny pores ) ( called ( ( stomata ( -LRB- ( ( ( singular , ) stoma ) -RRB- ) ) ) ( that ( ( control ( transpiration ( and ( gas exchange ) ) ) ) ( with ( the air ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NNS epidermis)) (VP (VBZ has) (NP (NP (JJ tiny) (NNS pores)) (VP (VBN called) (NP (NP (NN stomata)) (PRN (-LRB- -LRB-) (NP (NP (NN singular)) (, ,) (NP (NN stoma))) (-RRB- -RRB-)) (SBAR (WHNP (WDT that)) (S (VP (VBP control) (NP (NN transpiration) (CC and) (NN gas) (NN exchange)) (PP (IN with) (NP (DT the) (NN air)))))))))) (. .)))
The epidermis has tiny pores called stomata  (singular, stoma) that control transpiration and gas exchange with the air.
(ROOT (S (NP (NP (DT The) (NNS epidermis)) (PP (IN of) (NP (DT a) (NN leaf)))) (VP (VBZ contains) (NP (NP (NNS openings)) (VP (VBN known) (PP (IN as) (NP (NP (NN stomata)) (, ,) (SBAR (WHPP (IN through) (WHNP (WDT which))) (S (NP (NP (DT the) (NN exchange)) (PP (IN of) (NP (NNS gases)))) (VP (VBZ takes) (NP (NN place)))))))))) (. .)))