Biochem 2261 Exam 1 Quiz Questions With
Complete Solutions
Which organelle is the powerhouse of the cell and thus produces most of the ATP for the
cell. - ANSWER mitchondria
Absorption of drugs into the body is based on multiple factors including ionization state,
surface area of the stomach and intestines, and other physical properties of the drug. A
novel drug contains a carboxylic acid functional group with a pKa value of 3.24.. Based
on ionization states alone, would you predict that it is better absorbed (ie passes
through a lipid membrane) in the stomach where the pH is about 2, or in the small
intestines where the pH is about 8? - ANSWER In the stomach, because the acid form is
predominantly present.
A dialysis bag contianing 2M glucose is placed in a 4.5M NaCl solution. In which
direction does the water flow. - ANSWER out of the bag
A dialysis bag contianing 2M glucose is placed in a 2M NaCl solution. In which direction
does the water flow. - ANSWER out of the bag
Which range of pH is buffered by a oxalatic acid/sodium oxalate buffer? - ANSWER
3.3-5.3
Which of the following would act as a buffer system? Select all that apply - ANSWER
H3PO4 and NaH2PO4
, CH3COOH and KCH3COO
What ratio of 0.01M NaH2PO4 and 0.01 M Na2HPO4 are needed to prepare a buffer at
ph of 7.0? - ANSWER 1.5 NaH2PO4 : 1.0 Na2HPO4
Which mutation is most likely to disrupt biological activity? - ANSWER val to tyr
Proline - ANSWER has a rigid geometry that disrupts secondary structure
Cysteine - ANSWER forms disulfide bonds
Histidine - ANSWER can act as an acid or base depending on the environmental pH
Phenylalanine - ANSWER absorbs UV light at 280nm
what is the pI of glutamine? - ANSWER 5.65
What is the pI of arginine? - ANSWER 10.74
Which bond does not rotate? - ANSWER the peptide bond
Complete Solutions
Which organelle is the powerhouse of the cell and thus produces most of the ATP for the
cell. - ANSWER mitchondria
Absorption of drugs into the body is based on multiple factors including ionization state,
surface area of the stomach and intestines, and other physical properties of the drug. A
novel drug contains a carboxylic acid functional group with a pKa value of 3.24.. Based
on ionization states alone, would you predict that it is better absorbed (ie passes
through a lipid membrane) in the stomach where the pH is about 2, or in the small
intestines where the pH is about 8? - ANSWER In the stomach, because the acid form is
predominantly present.
A dialysis bag contianing 2M glucose is placed in a 4.5M NaCl solution. In which
direction does the water flow. - ANSWER out of the bag
A dialysis bag contianing 2M glucose is placed in a 2M NaCl solution. In which direction
does the water flow. - ANSWER out of the bag
Which range of pH is buffered by a oxalatic acid/sodium oxalate buffer? - ANSWER
3.3-5.3
Which of the following would act as a buffer system? Select all that apply - ANSWER
H3PO4 and NaH2PO4
, CH3COOH and KCH3COO
What ratio of 0.01M NaH2PO4 and 0.01 M Na2HPO4 are needed to prepare a buffer at
ph of 7.0? - ANSWER 1.5 NaH2PO4 : 1.0 Na2HPO4
Which mutation is most likely to disrupt biological activity? - ANSWER val to tyr
Proline - ANSWER has a rigid geometry that disrupts secondary structure
Cysteine - ANSWER forms disulfide bonds
Histidine - ANSWER can act as an acid or base depending on the environmental pH
Phenylalanine - ANSWER absorbs UV light at 280nm
what is the pI of glutamine? - ANSWER 5.65
What is the pI of arginine? - ANSWER 10.74
Which bond does not rotate? - ANSWER the peptide bond
