Give the correct biological only the term next to the question number.
1.2.1
The concentration of sense organs at the anterior end of an animal
leading to the formation of a head.
12.2 Blood filled cavity found in Arthropoda.
1.2.3 An animal phylum that lacks true tissues and organs.
1.2.4 The germ layer that gives rise to muscles and other internal organs,
other than the gut.
1.2.5 Animals that are attached to a substrate.
1.2.6 A rod-like structure in Chordata usually replaced with a vertebral
column.
12.7 Body cavity filled with fluid and lined with mesoderm.
1.2.8 An organism in which the body wall is made up of two layers of cells.
12.9 Organisms that use stinging cells and tentacles to catch their prey.
-2.10 Arrangement of the body such that cutting through the centre of the
structure in any direction produces two identical halves.​