In your own words explain why you think it is hard to restore ecosystems to their original conditions once they have shifted. Why doesn't re-introducing predators always 'fix' the trophic cascade? To answer this, think about some of the changes you have seen in ecosystems around the world and even in Maryland. Why can't we always restore balance?

Radiometric dating is used to tell the absolute age of materials by studying the decay rate of radioactive isotopes. the decay rates of isotopes are constant and are expressed as .

What is true of all organisms in the kingdoms protista, plantae, fungi, and animalia? a. they are multi-celled. b. they are photosynthetic. c. they have cells that contain membrane-bound organelles. d. they contain cells that lack membrane-bound organelles.

Label the steps for protein synthesis in order, beginning with the first steponce the protein is made, the gene for a particular trait is expressedmrna joins the ribosome, and the anticodons from trna join mrna to form a chain ofamino acidsrna polymerase unzips dna and free rna nucleotides join dna to form mrnav a chain of amino acids is formed from peptide bonds, creating a proteinmrna is transported from the nucleus of the cell to the ribosomes of the cell.