Oxygen is needed for the heart to oxygenate blood.
Burning? Idk it could be a few things. Lemme know if I’m right
Answer:
Explanation:
c each human being began as a single cells
Answer:
D)clues about the past climate of Earth
Explanation:
The fossil record certainly has gaps, mostly because the conditions required to create fossils have been rare ever since life began on Earth. A very small percentage of animals that have lived and died ever became fossils. Thus, many pieces of the puzzle are missing; some will never be found.
