According to the phylogeny tree, which phylum of organisms are most closely related to chordates?
cnidaria
nematoda
annelida
echinodermata
porifera
platyhelminthes mollusca
arthropoda
sponges jellyfish matworms round worms mollusk vegmented insects starfish
worms spiders
chordata
vertebrates
backbone
segmentation
endoskeleton
coelom
body cavity
bilateral symmetry
tissues
multicellularity
ancestral protist

1. seamount a raised footwall block between normal fault creates this 2. syncline break between rocks where a hanging wall rises relative to a footwall 3. hot spring on rolling hills, this a dip between hills 4. volcanic neck created when a block with hanging walls slips down between normal faults 5. caldera underwater volcano that never reaches above sea level 6. horst natural hot water on earth's surface containing many minerals 7. graben underwater volcano whose top is eroded flat by waves 8. crater less than a mile in diameter; looks like a bowl at the top of a volcano 9. guyot magma that filled the central vent that remains after the volcano has eroded 10. reverse fault over 1 mile in diameter; looks like a bowl over a volcano