The first known single-celled organisms appeared on Earth about 3.5 billion years ago, roughly a billion years after Earth formed. More complex forms of life took longer to evolve, with the first multicellular animals not appearing until about 600 million years ago.
Answer:
5 bases
Explanation:
If there are 17 amino acids and only 2 bases that can be combined in order to make a codon then:
for 4 bases 
is 16 and it is not enough combination for all 17 amino acids
for 5 bases 
is 25 combinations (meaning that more than one codon could code for the same amino acid).
<span>The S strain of bacteria that Griffith used was virulent meaning that when injected into the mouse, the mouse would die from pneumonia The R strain was nonvirulent and did not result in the death of the mouse. When Griffith injected mice with a dead S strain of pneumatic bacteria the mice remained healthy.
I hope this helps!
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Because water is a polar molecule, it makes an excellent solvent for polar and ionic compounds found within cells and tissues.
