Nuclear Membrane
The nuclear membrane is a double layer that encloses the cell's nucleus, where the chromosomes reside
They use tools to help take precise measurements, carry out experiments, and make observations.
Since 1910, the urban population has grown by nearly 500 percent while the rural population has grown by 19 percent. ... The Census Bureau estimates that during the same 30-year period, the population of the 49 states grew by more than 82 million people, or 36 percent