The nitrogen cycle provides nitrogen to the ecosystem from the atmosphere, ground and oceans. Nitrogen is an important component of complex molecules such as amino acids and nucleotides, which lead to the creation of proteins and DNA, the building blocks of all life .
Particle or Subatomic particle
<span>a bird flying from a tree</span>
Answer: <u><em>All living organisms are classified into groups based on very basic, shared characteristics. Organisms within each group are then further divided into smaller groups. The classification of living things includes 7 levels: kingdom, phylum, classes, order, families, genus, and species.</em></u>
Explanation:
Answer: elevation, index, contour interval
Explanation: