(1) As chemicals are passed up the food chain from plant to plant-eater, and from plant-eater to meat-eater, they become more and more concentrated in the tissues of each succeeding animal.
(chemicals; are passed up; from plant; to plant-eater) (they; become; more and more concentrated in the tissues of each succeeding animal)
chemicals they
are passed up become
from plant to plant-eater
more and more concentrated in the tissues of each succeeding animal