<span>A. If one essential nutrient within an ecosystem runs out, primary productivity will be limited.
A specific nutrient is need for every organism in the ecosystem. If this particular nutrient is diminished within the ecosystem then cellular processes will decreases and a great number of specie will die. </span>
I'm not sure if this is exactly correct, but to complete photosynthesis, plants need carbon dioxide and water. Usually sunlight as well. If you are supposed to be specific, you could put H2O. I hope I answered your question!
It’s b the pine tree has unprotected seeds, the apple tree has seeds in fruits
