BMB401 Exam I ID Page Practice Exam 1 SA Key Show all your work for questions that involve calculations 1 Please name one conservative substitution for the following do not use the same amino acid twice a Arg pos charged AA b Leu Branched AA c Asp Glu or Gln Asn d Thr Ser e Asn Gln Asp Glu 2 Please solve for pKa if pH 4 5 the concentration of A is 10 mM the concentration of HA is 100 M pH pKa log A HA 4 5 x log 10mM 0 1mM You an write this as 4 5 x log 10 1 mM 10 1 mM and you know that when you divide exponents you subtract them so we get 1 1 4 5 x log 10 So 4 5 x plus the log of 102 and all a log is is the number to which 10 is raised so the log of 2 10 2 4 5 X 2 therefore 2 5 X 3 Please solve for the charge on the peptide shown below at pH 2 and show your work 1 0 0 1 4 Please solve for G when S 100 J mole K T 298 K and H 0 1kJ mole Always write the equation First to receive partial credit G H T S G H T S where T is in Kelvin Put these in the same terms kilo Joule works for me So S is 0 1 kJ mole 1 K 1 G 0 1 kJ mole 1 298 K 0 1 kJ mole 1 K 1 G 0 1 kJ mole 1 29 8 kJ mole 1 29 7 kJ mole 1 5 Please identify the globin composition of a Adult hemoglobin alpha2 Beta 2 b Fetal hemoglobin alpha 2 Gamma2 EC What is the role of the distal histidine in hemoglobin function The distal His helps to regulate the entry and exit form the Fe2 O2 binding site Large molecules like CO2 have a harder time getting in and O2 is stabilized to leave as O2 and not superoxide O2 You had to mention both portions of these attributes entry and exit not just say it s a gatekeeper
View Full Document
Unlocking...