Answer:
The invention of the electron microscope allowed them to see organelles and other structures smaller than cells. There is variation in cells, but all cells have a plasma membrane, cytoplasm, ribosomes, and DNA. These similarities show that all life on Earth has a common ancestor in the distant past
Okay. The destruction of tundra vegetation will not really freeze the soil or deepen the active zone much. Therefore, A and C are eliminated. The destruction of the vegetation can actually melt permafrost, which contributes to global warming. The answer is D.
Prokaryotic cells reproduce asexually which makes it easier for them to multiply because all they have to do is split in half where as eukaryotic cells reproduce sexually so they have to find another cell to meet with in order to reproduce.
I think the answer is A) steroids
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