Atmospheric nitrogen varies widely from location to location, and local shortages occur frequently. b. atmospheric nitrogen cannot be used by most organisms. c. there is very little free nitrogen in the air. d. atmospheric nitrogen exists primarily in the stratosphere and does not come into contact with terrestrial ecosystems.

The development of_ factored in the development of complex organisms.

What feature of cell theory is best demonstrated in the image

Check all that apply diatoms are marine algae that have a shell made of silica, what are some of the uses of the silica shell after the diatoms die? 1.the shells make up the diatomaceous earth used in filters 2.it can be used as an ingredient in abrasives 3.they are used in food products 4.the shells can be used in some insulating materials