Targeting a DNA sequence for editing by the CRISPR‑Cas9 system requires that a protospacer‑adjacent motif (PAM) sequence appear just downstream of the target sequence. For S. pyogenes Cas9 this PAM is the trinucleotide NGG, where N represents any nucleotide. Assuming a fragment of DNA includes equal amounts of A, C, G, and T bases, how many bases apart, on average, would one expect to find the NGG PAM?

Examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. polyploidy is creating new species. the two populations are not interbreeding freely. hybrid offspring of the two populations begin to appear. one species will increase into a population size twice as large as the other species.

Ais a group of individuals of the same that exist together in the same place at the same time

Identify the composition of oceanic and continental crystal rocks. in a model of earth’s interior, where would these rocks appear?