I'm gonna say D is the answer.
Depend if you are more creative or more a solver(good in math).
Your answer would be... B. The climate on Earth has changed over time.
Answer:
The correct answer is "negative".
Explanation:
At pH 2 the net charge of the R groups of all the amino acids that comprise the peptide in question would be positive. This happens because of the high content of protons in a solution of pH 2, a value that is below the isoelectric point of all the amino acids. Since the peptide would have a positive net charge, it would migrate to the negative terminal of the gel because opposite charges attract each other.
Human,increase population and Overharvesting
