BIOC 431 EXAM 1 QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2025
What is the pH of a solution which the [H+] is 9x10^-7? - Answers 6.05
What is the pH of a mixture of 0.05 M NaH2PO4 and 0.081 M Na2HPO4 (pka=6.86)? If 2.0 mL of
10 N HCl is added to 1 L of this mixture, what will be the new pH? - Answers 1) 7.07
2) 6.8
CO2 is dissolved in the blood to form H2CO3 which results in a conjugate base that consists of
HCO3- and the acid considered CO2. What is the concentration ration of HCO3- and CO2 in the
blood at pH 7.3 (pKa= 6.2)? - Answers 12.6
What is the molarity of [H+] in a solution where [OH-] is 6x10^-10 M? - Answers 1.7x10^-5 M
Which part of the muscle does not decrease in size during concentration? - Answers A-band
Draw the structure and single letter symbol for Aspartate (pKa of side group= 3.9) at pH 7 -
Answers D
Draw the structure and single letter symbol for methionine at pH 7 - Answers M
Draw the structure and single letter symbol for isoleucine at pH 7 - Answers I
Draw the structure and single letter symbol for lysine (pka of side=10.5) at the pH 7 - Answers K
Draw the structure and single letter symbol for tyrosine (pKa of side group=10.46) at pH 7 -
Answers Y
What is the charge of amino acids in the following pH environments in which the pKa of the
amino end is 9.7 and the carboxy end is 2.3?
Arg pKa = 12.5
@pH 2
@pH 5.5
@pH 11 - Answers +2
+1
0
What is the charge of amino acids in the following pH environments in which the pKa of the
amino end is 9.7 and the carboxy end is 2.3?
Lys pKa = 10.5
, @pH 2
@pH 5.5
@pH 11 - Answers +2
+1
-1
What is the charge of amino acids in the following pH environments in which the pKa of the
amino end is 9.7 and the carboxy end is 2.3?
His pKa = 6.0
@pH 2
@pH 5.5
@pH 11 - Answers +2
+1
-1
What is the charge of amino acids in the following pH environments in which the pKa of the
amino end is 9.7 and the carboxy end is 2.3?
Glu pKa = 4.1
@pH 2
@pH 5.5
@pH 11 - Answers +1
-1
-2
T/F Formation of the peptide bond is a condensation reaction in which water is a by-product. -
Answers True
What is a zwitterion? - Answers a zwitterion is a species with both a positive and a negative
charge but has a net neutral charge
Explain how the peptide bond contains a dipole. How does the dipole work in stabilizing an
alpha helical structure? - Answers Oxygen is more electronegative than nitrogen, so it draws
electrons away from nitrogen and toward itself. Therefore there are dipole moments throughout
What is the pH of a solution which the [H+] is 9x10^-7? - Answers 6.05
What is the pH of a mixture of 0.05 M NaH2PO4 and 0.081 M Na2HPO4 (pka=6.86)? If 2.0 mL of
10 N HCl is added to 1 L of this mixture, what will be the new pH? - Answers 1) 7.07
2) 6.8
CO2 is dissolved in the blood to form H2CO3 which results in a conjugate base that consists of
HCO3- and the acid considered CO2. What is the concentration ration of HCO3- and CO2 in the
blood at pH 7.3 (pKa= 6.2)? - Answers 12.6
What is the molarity of [H+] in a solution where [OH-] is 6x10^-10 M? - Answers 1.7x10^-5 M
Which part of the muscle does not decrease in size during concentration? - Answers A-band
Draw the structure and single letter symbol for Aspartate (pKa of side group= 3.9) at pH 7 -
Answers D
Draw the structure and single letter symbol for methionine at pH 7 - Answers M
Draw the structure and single letter symbol for isoleucine at pH 7 - Answers I
Draw the structure and single letter symbol for lysine (pka of side=10.5) at the pH 7 - Answers K
Draw the structure and single letter symbol for tyrosine (pKa of side group=10.46) at pH 7 -
Answers Y
What is the charge of amino acids in the following pH environments in which the pKa of the
amino end is 9.7 and the carboxy end is 2.3?
Arg pKa = 12.5
@pH 2
@pH 5.5
@pH 11 - Answers +2
+1
0
What is the charge of amino acids in the following pH environments in which the pKa of the
amino end is 9.7 and the carboxy end is 2.3?
Lys pKa = 10.5
, @pH 2
@pH 5.5
@pH 11 - Answers +2
+1
-1
What is the charge of amino acids in the following pH environments in which the pKa of the
amino end is 9.7 and the carboxy end is 2.3?
His pKa = 6.0
@pH 2
@pH 5.5
@pH 11 - Answers +2
+1
-1
What is the charge of amino acids in the following pH environments in which the pKa of the
amino end is 9.7 and the carboxy end is 2.3?
Glu pKa = 4.1
@pH 2
@pH 5.5
@pH 11 - Answers +1
-1
-2
T/F Formation of the peptide bond is a condensation reaction in which water is a by-product. -
Answers True
What is a zwitterion? - Answers a zwitterion is a species with both a positive and a negative
charge but has a net neutral charge
Explain how the peptide bond contains a dipole. How does the dipole work in stabilizing an
alpha helical structure? - Answers Oxygen is more electronegative than nitrogen, so it draws
electrons away from nitrogen and toward itself. Therefore there are dipole moments throughout
