Problem

Solutions For 9780131905429 Chapter 3 Problem 23A

Step-by-Step Solution

Solution 1

The growth of all organisms depends on the availability of mineral nutrients, and none is more important than nitrogen, which is required in large amounts as an essential component of proteins, nucleic acids and other cellular constituents. There is an abundant supply of nitrogen in the earth’s atmosphere – nearly 79% in the form of gas. However, is unavailable for use by most organisms because there is a triple bond between the two nitrogen atoms, making the molecule almost inert. In order for nitrogen to be used for growth it must be “fixed” (combined) in the form of ammonium or nitrate ions.

Step #2 of 6

Microorganisms have a central role in almost all aspects of nitrogen availability and thus for life support on earth.

Step #3 of 6

1) Some bacteria can convert into ammonia by the process termed nitrogen fixation; these bacteria are either free living or form symbiotic associations with plants or other organisms (Example – Termites, protozoa).