animals are
multicellular and hetertrophic
some animals reproduce
asexually
sponges have no
true tissue and no body symmetry
similar parts branch out in all directions from a central line
radial symmetry
animals with similar halves
bilateral symmetry
animals have _ germ layers
3
invertebrates have no
body symmetry or are radially or bilaterally symmetrical
all vertebrates have an
endoskeleton
some invertebrates have an
exoskeleton
during cleavage (1st step)
cells divide repeatedly
mass of cells produced by cleavage form the
blastula
the germ layers are defined during
gastrula formation
acoelomates have
no body cavity
psuedocoelomates have
a body cavity
coelomates have a
coelom