The oxygen in the upper atmosphere combine to form ozone layer (o3) that allows to colonize surface water.
Explanation:
The fossil stomatolites are formed at about 3.0 ga laminated bacteria. they form the sediments to fall into a thin film of bacteria, these bacteria binds with the sediment and grows through it.
Cynobacteria uses water, CO2 and sunlight to create their own food and produce oxygen as a by product. The significance of stromatolites is that they are earliest fossil evidence life on earth.
They were first organism to photosynthesis and produce oxygen.
Medulla which is also part of the brain stem so your answer is brain stem :D<span />
Because it’s a lot faster and cheaper and most hospital don’t take insurance but ERs do
Answer:
legs
Explanation:
I like walking with friends
