amino acids and peptides

Question 1

how is a dipeptide formed

Answer 1

dipeptide: 2 amino acids joined tgt by peptide bonds

-NH3+ group of one animo acid foms an amide bond with the carboxylate of another amino acids
H2O is removed

Question 2

what is the C terminal amino acid in the tetrapeptide glycylalalanyisoleucymethionine

Answer 2

methionine

Question 3

what is the charge on a zwitterion

Answer 3

neutral

Question 4

what is the charge on an amino acid at a pH below its pI

Answer 4

positive

Question 5

what is the simplest amino acid

Answer 5

glycine