If the magma chamber empties what could be formed?

When analyzing tree rings, what do scientists assume a thin ring indicates?

Which of these correctly describes the difference between processes that take place in prokaryotic and eukaryotic cells?

Pls me i need this ! each cell has genes activated depending on it's job and what kind of cell it is. it is the presence of that causes the repressor protein to fall off and unblock the gene on the lac operon. if a gene is turned on then it is being an additional circular chromosome found in some bacteria that is used in genetic engineering.