( ( ( ( ( ( The ( collective term ) ) ( for ( ( the petals ) ( of ( a flower ) ) ) ) ) ( is ( the corolla ) ) ) and ) ( ( each ( of ( the petals ) ) ) ( is ( called ( a lobe ) ) ) ) ) . )
(ROOT (S (S (NP (NP (DT The) (JJ collective) (NN term)) (PP (IN for) (NP (NP (DT the) (NNS petals)) (PP (IN of) (NP (DT a) (NN flower)))))) (VP (VBZ is) (NP (DT the) (NN corolla)))) (CC and) (S (NP (NP (DT each)) (PP (IN of) (NP (DT the) (NNS petals)))) (VP (VBZ is) (VP (VBN called) (NP (DT a) (NN lobe))))) (. .)))
The collective term for the petals of a flower is the corolla and each of the petals is called a lobe.
(ROOT (S (NP (NP (DT All)) (PP (IN of) (NP (DT the) (NNS petals)))) (ADVP (RB together)) (VP (VBP are) (VP (VBN called) (NP (DT a) (NN corolla)))) (. .)))
All of the petals together are called a corolla.