Which of the following features are true of all three types of worms (flatworms, roundworms, and annelids)?

Select all that apply.

closed circulatory system
true coelom
bilateral symmetry
cephalization
three tissue layers

above statement is not a true statement about the open ocean because the open ocean has low levels of nutrients. most of the photosynthetic activity on earth occurs in the open ocean within the photic zone. organisms in the deep ocean are exposed to frigid temperatures and total darkness but it does not begin at the low-tide mark.