Anerobic organisisms need to make oxoygen just like photosynetheic plants
This would be a D) "physical model."
It's not natural, because it's not out in nature.
It's not conceptual because that would just be ideas, arbitrary compared to physical ones.
And it's not mathematical, because that would only involve equations, graphs, and tables.
sunlight would be the answer to your question
Instead of seeds they produce spores. My names Gary Winthorpe and you can ask me any questions you want ;)
Answer:
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Explanation:
Well the arteries carry oxygen and your nutrients away from you heart, to ypur bodies tissues. The viens take oxygen poor blood back to the heart. Arteries begin with the aorta, the large artery leaving the heart. They carry oxygen rich blood away from the heart to all the bodies tissues.