In a nucleotide, to which carbon in the sugar is the base attached?

What did not occur in the proterozoic eon a)the oxygen levels increase greatly in the atmosphere, b)the emergence of the eukarya , c)muti cella’s eukaryotic organisms began to diversify, d)anaerobic bacteria kept thriving with more oxygen

In which layer do organisms on earth love?

Can ground tissue do photosynthesis