( We ( ( ( are also ) ( studying ( organelles ( known ( as ( ( mitochondria , ) ( which ( are ( ( the ( power plants ) ) ( of ( mammalian cells ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP We)) (VP (VBP are) (ADVP (RB also)) (VP (VBG studying) (NP (NP (NNS organelles)) (VP (VBN known) (PP (IN as) (NP (NP (NN mitochondria)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBP are) (NP (NP (DT the) (NN power) (NNS plants)) (PP (IN of) (NP (JJ mammalian) (NNS cells))))))))))))) (. .)))
We are also studying organelles known as mitochondria, which are the power plants of mammalian cells.
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