2. VERTEBRATES
derived its name from vertebrae, the
series of bones that make up the
backbone or the vertebral column
subphylum of Chordata, which are
bilaterally symmetrical
Chordates are named for skeletal
structure, the notochord
Notochord is a longitudinal, flexible,
rod located between the digestive tube
and the nerve cord
25. SPONGES
phylum Porifera
suspension feeders living in both
spongocoel pores in the central cavity
osculum larger opening
choanocytes collar cells (named for
the membranous collar around the base
of the flagellum
consist of two layers
Mesohyl gelatinous region
Amoebocytes