It is the first option. Atmospheric nitrogen is very stable so there fore hard to react with. But bacteria contain molecules that can break the bond of nitrogen.
B.)Ecosystem
A community resides within an ecosystem, a population within a community, and an individual within a population
The answer: Yes, because plants photosynthesis to absorb Carbon Dioxide and convert it in to Oxygen. We humans breathe the oxygen that is produced from plants.
Each cell is alive even if it is part of a multi celled body, and all living organisms consist of one or more cells. Also, cells reproduce by dividing so it follows that all existing cells must have arisen by division of other cells. As a cell divides it passes it hereditary material- its DNA- to offspring.
C hope that helps have a good one
