BIOC 384 Smartwork 07 (SW-07) 2026 | Most Tested
Questions & Verified Answers | Latest Update | Graded A+
1. What structural feature predominantly characterizes the β2-adrenergic
receptor?
mostly α helices
none of the above
mostly β turns
mostly β sheets
2. Which of the following can affect a protein's stability?
pH
Temperature
Presence of proteases
All of the above
3. What type of hormone acts on the same cell that secretes it?
Nitric oxide
Endocrine hormones
Paracrine hormones
Autocrine hormones
4. If a mutation in Gqα disrupts the three α helices, what effect would this likely
have on GDP binding?
GDP would not be held in place effectively.
GDP would bind covalently to Gqα.
, GDP binding would increase significantly.
GDP would be hydrolyzed more rapidly.
5. If a researcher observes a Lineweaver-Burk plot where the lines intersect on
the y-axis, what type of enzyme inhibition is likely occurring?
Non-competitive inhibition
Uncompetitive inhibition
Allosteric inhibition
Competitive inhibition
6. Which of the following correctly describes the biochemistry of the amino
acids at the termini of pepsin?
two charged amino acids at the N-terminus and two nonpolar amino
acids at the C-terminus
two nonpolar amino acids at the N-terminus and one polar amino
acid at the C-terminus
three polar amino acids at the N-terminus and one charged amino
acid at the C-terminus
three charged amino acids at the N-terminus and two polar amino
acids at the C-terminus
7. Arrange the events in the pathway activated by G-protein-coupled receptors
(GPCRs) in the correct order. 1. Activation of effector 2. Activation of protein
kinases 3. Receptor binds first messenger 4. Production of second messenger
5. Activation of G protein
2→3→5→4→1
3→5→2→4→1
, 3→5→1→4→2
3→1→5→4→2
1→3→5→2→4
8. Describe the significance of α helices in the structure of the β2-adrenergic
receptor and their role in its function.
The α helices prevent the receptor from interacting with other
proteins.
The α helices are irrelevant to the receptor's function.
The α helices contribute to the receptor's stability and facilitate the
binding of ligands.
The α helices are responsible for the receptor's enzymatic activity.
9. If you look at a bright light and quickly close your eyes, the retinal molecules
quickly turn off that visual signal to the brain. Which of the following do you
think is the best explanation for such an observation?
The G proteins, once activated, are separated into α and βγ subunits
and this terminates the signal.
Termination of the visual signal is completely dependent on removal
of rhodopsin from the plasma membrane.
Inhibition of the visual signal requires GTPase activating proteins
(GAP) binding and GTP hydrolysis.
Guanine nucleotide exchange factors, or GEFs, are slow to respond in
order to reactivate the G proteins.
10. What are the two terminal ends of the Gqα protein called?
Hydrophobic and hydrophilic ends
Questions & Verified Answers | Latest Update | Graded A+
1. What structural feature predominantly characterizes the β2-adrenergic
receptor?
mostly α helices
none of the above
mostly β turns
mostly β sheets
2. Which of the following can affect a protein's stability?
pH
Temperature
Presence of proteases
All of the above
3. What type of hormone acts on the same cell that secretes it?
Nitric oxide
Endocrine hormones
Paracrine hormones
Autocrine hormones
4. If a mutation in Gqα disrupts the three α helices, what effect would this likely
have on GDP binding?
GDP would not be held in place effectively.
GDP would bind covalently to Gqα.
, GDP binding would increase significantly.
GDP would be hydrolyzed more rapidly.
5. If a researcher observes a Lineweaver-Burk plot where the lines intersect on
the y-axis, what type of enzyme inhibition is likely occurring?
Non-competitive inhibition
Uncompetitive inhibition
Allosteric inhibition
Competitive inhibition
6. Which of the following correctly describes the biochemistry of the amino
acids at the termini of pepsin?
two charged amino acids at the N-terminus and two nonpolar amino
acids at the C-terminus
two nonpolar amino acids at the N-terminus and one polar amino
acid at the C-terminus
three polar amino acids at the N-terminus and one charged amino
acid at the C-terminus
three charged amino acids at the N-terminus and two polar amino
acids at the C-terminus
7. Arrange the events in the pathway activated by G-protein-coupled receptors
(GPCRs) in the correct order. 1. Activation of effector 2. Activation of protein
kinases 3. Receptor binds first messenger 4. Production of second messenger
5. Activation of G protein
2→3→5→4→1
3→5→2→4→1
, 3→5→1→4→2
3→1→5→4→2
1→3→5→2→4
8. Describe the significance of α helices in the structure of the β2-adrenergic
receptor and their role in its function.
The α helices prevent the receptor from interacting with other
proteins.
The α helices are irrelevant to the receptor's function.
The α helices contribute to the receptor's stability and facilitate the
binding of ligands.
The α helices are responsible for the receptor's enzymatic activity.
9. If you look at a bright light and quickly close your eyes, the retinal molecules
quickly turn off that visual signal to the brain. Which of the following do you
think is the best explanation for such an observation?
The G proteins, once activated, are separated into α and βγ subunits
and this terminates the signal.
Termination of the visual signal is completely dependent on removal
of rhodopsin from the plasma membrane.
Inhibition of the visual signal requires GTPase activating proteins
(GAP) binding and GTP hydrolysis.
Guanine nucleotide exchange factors, or GEFs, are slow to respond in
order to reactivate the G proteins.
10. What are the two terminal ends of the Gqα protein called?
Hydrophobic and hydrophilic ends
