Answer:
what are we supposed to help you with
A. There were animals 3 billion years ago; they just weren't fossilized. B. Animals are warm-blooded; the ocean was too cold for animals.
Decomposers
Producers
Primary consumers
Secondary consumers
Tertiary consumers
Answer:
Xylem,phloem and tissues from vascular systems produce stem
Xylem + phloem+ tissues from vascular systems = stem ( transport systems)