( ( The urea ) ( ( is ( ( ( ( ( formed ( in ( the liver ) ) ) , ) ( ( ( ( ( transferred ( to ( the blood ) ) ) , ) and ) then ) ( ( removed ( from ( the blood ) ) ) ( by ( the kidney ) ) ) ) ) and ) ( excreted ( with ( the urine ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN urea)) (VP (VBZ is) (VP (VP (VBN formed) (PP (IN in) (NP (DT the) (NN liver)))) (, ,) (VP (VP (VBN transferred) (PP (TO to) (NP (DT the) (NN blood)))) (, ,) (CC and) (ADVP (RB then)) (VP (VBN removed) (PP (IN from) (NP (DT the) (NN blood))) (PP (IN by) (NP (DT the) (NN kidney))))) (CC and) (VP (VBN excreted) (PP (IN with) (NP (DT the) (NN urine)))))) (. .)))
The urea is formed in the liver, transferred to the blood, and then removed from the blood by the kidney and excreted with the urine.
(ROOT (S (NP (NNP Urea)) (VP (VBZ is) (VP (VP (VBN made) (PP (IN in) (NP (DT the) (NN liver)))) (CC and) (VP (VBN excreted) (PP (IN in) (NP (NN urine)))))) (. .)))
Urea is made in the liver and excreted in urine.