Question

why is nitrogen essential for plants?
it is a key component of proteins and dna.
it provides energy for growth.
it protects plants from predators.
it helps plants absorb water.

Explanation:

Nitrogen is a crucial element for plants as it is a key component of proteins (which are involved in various biological processes like enzyme - catalyzed reactions) and DNA (the genetic material that controls plant growth, development, and reproduction). Energy for plant growth is mainly provided by processes like photosynthesis (which converts light energy into chemical energy in the form of glucose). Protection from predators is usually achieved through physical structures (like thorns) or chemical defenses (like secondary metabolites), not nitrogen. Absorption of water is mainly related to the structure of the root system and processes like osmosis.

Answer:

It is a key component of proteins and DNA.