Answer:the decline of lichens is an important indicator of an imbalance in the ecosystem. this research can help system ecologists predict how pollution will affect the entire ecosystem
Explanation:
TRNA: transport/transfer rna
Answer:
Signposts that determine the fate of cells.
Explanation:
Embryos for humans and other animals often look alike at certain developmental stages because they share ancient genes. This expression means that a more advanced organism, like humans, will resemble less advanced species during it's development stages.
The correct answer is mRNA.
mRNA or messenger RNA is synthesized during the process of transcription, from DNA molecule which is used as a template. mRNA contains information about protein synthesis (translation) in the form of nucleotide triplets or codons.
In the example above: reference book is DNA molecule (template for copies), copies are mRNA, wood is amino acids (building blocks) and doghouse is protein.
The older the Earth's crust, the denser it is.