Which structural components of an amino acid contribute to its zwitterionic nature at physiological pH?

How does the pH of a solution relative to the pKa of an amino group affect its protonation state?

At physiological pH, what is the net charge of a zwitterion?

Why do amino acids with non-ionizable R groups have only two pKa values?

Which property is unique to ionizable R groups compared to non-ionizable R groups?

How does the ionization state of an R group affect protein structure?

What is the isoelectric point (pI) of a molecule?

How does the isoelectric point affect a molecule's behavior in an electric field?

What is the relationship between the acidity of an amino acid and its isoelectric point?

How does the middle pKa value help in identifying the pH region for a neutral net charge?

What does the equivalence point on a titration curve indicate?

Which of the following amino acids has an ionizable R group?

Which of the following is a prerequisite for understanding the Henderson-Hasselbalch equation?

Which concept is essential for understanding the Henderson-Hasselbalch equation?