the answer should be A replication
Oxygen and sugar. Or in terms of compounds, O2 and C6H12O6
-Not completely understood, share echinoderm and chordate characteristics
-Chordates/them have pharnygeal slits
-Ambulacraria hypothesis unites echinoderms and hemichordates on the basis of a shared diffuse epidermal nervous system
-Shared tripartite coelom in hemichordates/echinoderms
-Buccal diverticulum now believed to be a synapomorphy of hemichordates only
-Early embryogenesis of hemichordates similar to echinoderms
-Tornaria larva almost identical to bipinnaria larva, suggesting that hemichordates/echinoderms are sister groups
<span>-Sequence analysis of the gene encoding the small subunit of rRNA supports a deuterostome clade</span>