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.
Answer:
the food web
Explanation: A food web is a conceptual model that represents the flow of energy through an ecosystem.
1.) Cladogram
2.) taxonomy
Irritation Threshold is defined as the name applies. It is the threshold or maximum point at which an individual has become irritated or annoyed.
<span>The correct answers are that it lacks cells, DNA, and cannot maintain homeostasis. It doesn't have any organic matter and homeostasis is impossible because it would turn off eventually. It doens't have DNA and it doesn't reproduce. It's just plasma and it is not a living being, it just moves because of the chemical reactions that occur. </span>
