Answer:
Index
Explanation:
An index fossil can be used to identify a specific period of time. Organisms that make good index fossils are distinctive, widespread, and lived briefly. Their presence in a rock layer can be used to identify that period of time over a large area.
Answer: UAC
Explanation: transfer RNA(tRNA) is the type of RNA that interprets the messenger RNA(mRNA) code during translation. The job of tRNA is to match up the amino acids with the correct codons in the mRNA strand. According to the base pair rule for RNA, Adenine and Uracil (A - U) are base complements while Guanine and Cytosine (G - C) are base complements. So if;
mRNA: AUG
then,
tRNA: UAC.
