What was the first life form? plant, animal, or bacteria?

What is believed to be the first single cell life form? bacteria, plant, or animal cell? if it was an animal type cell wouldn't it have to reverse it's evolution for plants to appear since plants are a simpler life form? Then bacteria DNA, is not a double helix, how would that fit in to life evolving to better itself. Why would a cell with no capability of thought or emotion not just die off, the very thought that self preservation and procreation seems to indicate a logical progression. Why would eyesight happen when no comprehension that there is anything to see or comprehension of light to see things by was present?
Asked Nov 18, 2013

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