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.

The large ground finch obtains food by cracking seeds. what is its short, strong beak an example? a) tendency toward perfection b) adaptation of a species over time c) selective use and disuse of an organ over time d) scarcity of recourses

(drag each tile to the correct location.) categorize each term as something that is typical of a scientific theory, a scientific hypothesis, or both. - a tentative statement used to guide scientific investigations. - makes predictions about future events. - can be tested by many independent researchers. - based on observations of natural phenomena. - a well-established, highly reliable explanation.

2. sketch the inside of the bean nodule, and describe or label what you observed with the hand lens.