During nitrogen fixation, specialized bacteria living in Earth’s convert nitrogen taken from the into ammonia. Another set of bacteria convert the ammonia to compounds called nitrates that plants and animals can use.

In descriptive writing, the conclusion should introduce a new idea return the discussion to the general level use a quotation explain why the essay was effective

The greatest gift the sumerians gave the world was the invention of writing. the sumerians were a wealthy people. they needed some way to keep track of what they owned. they began drawing pictures. they used a reed as a pen. they drew on soft pieces of clay. the soft clay was then dried in the sun. the tablet became a permanent record. later, the sumerian drawings changed into wedge-shaped symbols. this kind of writing is called cuneiform. by putting symbols together, the sumerians could write entire sentences.

The room was gaudy with its leather couch and purple walls