Which pair of statements best describes an essential amino acid?
it is an amino acid that contains peptide bonds. an example is proline.
it is an amino acid that contains nitrogen. an example is aspartic acid.
it is an amino acid that cannot be made by the body. it must be obtained from eating certain foods.
it is an amino acid that can be produced by the body. vitamin supplements maintain healthy levels

C

Explanation:

It is an amino acid that cannot be produced by the body. It must be obtained from eating certain foods.

volcanoes (an event in the geosphere) release a large amount of particulate matter into the atmosphere. these particles serve as nuclei for the formation of water droplets (hydrosphere). rainfall (hydrosphere) often increases following an eruption, stimulating plant growth (biosphere).

the darker peppered moth species were favored due to the fact that the industrial revolution had made all the nearby trees a darker color instead of white.