Answer:
Section 3.2Primary Structure: Amino Acids Are Linked by Peptide Bonds to Form Polypeptide Chains. Proteins are linear polymers formed by linking the α-carboxyl group of one amino acid to the α-amino group of another amino acid with a peptide bond (also called an amide bond).
Answer:
Imagine studying a cell. That cell has billions of things you can learn about. Now imagine 37.2 trillion cells each a little bit different but still similar. Now imagine that multiplied by all the different people there are on earth. Now then include all the other types of living animals.
That's biology
2 is crescent and 4 is gibbous