True, the plasma membrane is selectively permeable and controls the various substances that are allowed into the cell and that are allowed to leave the cell.
Answer: Radiometric dating
Explanation: Radiometric dating is a procedure used to determine the age of elements such as rocks and fossils. It is based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates.
Answer:
6, 3, 4, 5, 7, 2, 1
Explanation:
Here, speciation occurs because the original butterfly population gets separated into two populations, each facing a different set of environmental conditions. Initially, there was just a single population of butterflies in the valley and all butterflies were able to mate with each other. A fire destroyed their habitat so they had to migrate to other areas. Some butterflies migrated to eastern side of mountain and some to western side of mountain.
Now there were two butterfly populations and they faced different environment from each other. Over the time, the populations adapted to their local surroundings and started to accumulate changes in their genome. Their gene pools started to separate from each other. Eventually they evolved into two different species. When their old habitat was restored in the valley, they returned once again. However, this time they were not able to interbreed because they were now two different species.
Answer:
Replicating DNA is fragile, and can break during the duplication process. In fact, broken chromosomes are often the source of DNA rearrangements and can change the genetic program of a cell. These changes can trigger a growth advantage in a single cell in your body, and when that cell continues to divide, tumors arise. Fortunately, our cells have defense mechanisms to shield us from these damaging events.
All the outer planets have low density's. You can't walk on any of the outer planets because you would fall right through them because they aren't dense.
