The external cell membrane. Even organisms as simple as bacteria have a cell membrane.
Prokaryotes do not have internal membranes but they still have external membranes.
Everything living thing has a cell membrane
Your answer should be lakes and forests. Acid precipitation will rot out forests because of the acid content and in lakes it raises the PH balance making it more acidic which in turn makes it harder for anything to live in these lakes or drink from them. (Hope this helps ^-^)
At the current rate of uranium consumption with conventional reactors, the world supply of viable uranium, which is the most common nuclear fuel, will last for 80 years. Scaling consumption up to 15 TW, the viable uranium supply will last for less than 5 years
Axon, dendrite
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