Describe the appearance and structure of DNA.

it’s a made up of molecules called nucleotides. Each nucleotides contain a phosphate group, a sugar group and nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G), and cytosine (C)

Explanation:

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.

a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.