Frog's heart<span> has one ventricle, while humans have 2, hence deoxygenated blood from body mixes with the oxygenated blood coming from lungs.
Source: S</span><span>ocratic</span>
Fossils could not be found in that layer of rock
Put simply, water evaporates from the land and sea, which eventually returns to Earth as rain and snow. Climate change intensifies this cycle because as air temperatures increase, more water evaporates into the air. Warmer air can hold more water vapor, which can lead to more intense rainstorms, causing major problems like extreme flooding in coastal communities around the world.
https://www.climaterealityproject.org/blog/climate-change-impacting-water-cycle
Answer:
I believe your answer to this question is B. They are visible with a light microscope.
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