Invertebrate Diversity Crossword

After a sperm fertilizes an egg, the zygote undergoes rapid cell division
Cleavage leads to formation of a multicellular, hollow
The blastula undergoes gastrulation, forming a __________ with different layers of embryonic tissues
Animals can be categorized according to ______ ______ – a set of morphological and developmental traits
Two-sided symmetry is called
During development, three germ layers give rise to the tissues and organs of the animal embryo
_______ is the germ layer covering the embryo’s surface
_________ is the innermost germ layer and lines the developing digestive tube, called the archenteron
Most triploblastic animals possess a
A true body cavity is called a _______ and is derived from mesoderm
Triploblastic animals that possess a pseudocoelom are called __________________.
Triploblastic animals that lack a body cavity are called ____________.
animals in which the mouth develops from the blastopore
_____________ are animals that lack a backbone
____________ are specialized organelles within cnidocytes that eject a stinging thread