Teaching Haryana (HPSC) Assistant Professor Mock Test 2025 Life Sciences Biochemistry Conformation of Proteins and Nucleic acids
If an amino acid with an ionizable side chain (R-group) is titrated from pH 0 to 14, which of the following ionizable states is least likely to be observed during the entire titration?
1
All groups protonated (–NH3⁺, –COOH, and R-H⁺)
2
Zwitterionic state with neutral R-group (–NH3⁺, –COO⁻, and R-H)
3
Net negative charge with deprotonated R-group (–NH2, –COO⁻, and R⁻)
4
Zwitterionic state with ionized R-group resulting in a net positive charge (–NH3⁺, –COO⁻, and R⁺)
5
Question Not Attempted