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vietquocnguyen vietquocnguyen
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Posts: 498
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6 years ago
The two nucleotide sequences are
 
  a. identical
  b. 80 to 90 the same
  c. 80 to 90 different
  d. none of the above

Question 2

When the photosynthetic organisms evolved the ability to split water, they produced _____ as a waste material, which was poisonous to most of the cells then alive.
 
  a. hydrogen gas
  b. hydrogen sulfide
  c. water
  d. carbon dioxide
  e. oxygen
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wrote...
6 years ago
Answer to q. 1

d

Answer to q. 2

E; The earliest photosynthesizers used H2, H2S, and other sources of hydrogen atoms. Only when cells developed processes for splitting water did they begin to release O2 as a by-product.
wrote...
6 years ago
Tremendous help, I just double-checked it with my friend Smiling Face with Open Mouth
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