There are all sorts of ways to reconstruct the history of life on Earth. Pinning down when specific events occurred is often tricky, though. For this, biologists depend mainly on dating the rocks in which fossils are found, and by looking at the “molecular clocks” in the DNA of living organisms.
There are problems with each of these methods. The fossil record is like a movie with most of the frames cut out. Because it is so incomplete, it can be difficult to establish exactly when particular evolutionary changes happened.
Modern genetics allows scientists to measure how different species are from each other at a molecular level, and thus to estimate how much time has passed since a single lineage split into different species. Confounding factors rack up for species that are very distantly related, making the earlier dates more uncertain.
These difficulties mean that the dates in the timeline should be taken as approximate. As a general rule, they become more uncertain the further back along the geological timescale we look. Dates that are very uncertain are marked with a question mark.
Heterotrophs, primary consumers, and herbivores..
Answer:
Gene therapy
Explanation:
Gene therapy can be defined as the methodologies used to modify/restore the expression of target genes and thus cure and treat genetic disorders. Gene therapy approaches consist of delivering specific nucleic acids (either RNA or DNA) in the cells of the individual to be treated. Some of the most important gene therapy approaches include the use of small interfering RNAs (siRNAs) in order to block target gene expression, adenovirus vectors to insert genes into host cells, the use of the CRISPR-Cas9 genome editing system to insert specific sequences by the mechanism of homologous recombination, etc.
Answer: supersaturated
Explanation: A supersaturated solution is a solution in which the dissolved solute is more than the solvent can hold at that particular temperature.
A solution is a substance which sontains a dissolved solute. A solution can be saturated, unsaturated or supersaturated.
A saturated solution contains the maximum amount of dissolved solute a solvent can hold at that temperature.
An unsaturated solution contains less amount of solute than the solvent can hold at that temperature, this means that more solute can still dissolve in the solution.
A supersaturated solution contains more solute that can be dissolved in the solvent at that temperature.
