Oxygen and food are carried to tissues, and carbon dioxide and chemical (nitrogenous) waste are transported from tissues to excretory organs for disposal ( excretion ).
(Oxygen and food; are carried; to tissues) (carbon dioxide and chemical (nitrogenous) waste; are transported; from tissues; to excretory organs; for disposal)
Oxygen and food carbon dioxide and chemical (nitrogenous) waste
are carried are transported
to tissues
from tissues to excretory organs for disposal