CELL BIOCHEM FINAL EXAM WITH
COMPLETE QUESTIONS AND 100%
CORRECT ANSWERS { GRADED A+}
How is the asymmetrical distribution of phospholipids across the
plasma membrane created? - ✔✔ABC transporters called flippases
move them between the cytosolic and luminal leaflets of the ER
membrane
Which of the following is FALSE regarding bacteriorhodopsin? - ✔✔it
pumps protons into of the cytosol
Which of following modifications would result in increased membrane
fluidity? - ✔✔increased amount of unsaturation of fatty acid tails
,How is phosphatidylserine different from all other phospholipids? -
✔✔it is negatively charged at neutral pH
Which of the following proteins transports sodium ions against their
concentration gradient? - ✔✔sodium-potassium ATPase
Which of the following organelles is responsible for the synthesis of
new membrane for components of the endomembrane system? -
✔✔endoplasmic reticulum
Which of the following proteins is/are NOT (an) ABC transporter(s)? -
✔✔calcium ATPase
In epithelial cells, how is glucose transported across the apical
membrane? - ✔✔sodium-glucose symporter
The resting potential of the plasma membrane of an excitable cell is
primarily due to the selective permeability of the membrane to which
of the following ions? - ✔✔potassium ions
,True or False? "Only the extracellular domains of membrane
glycoproteins can be glycosylated." - ✔✔True
For which of the following ions is the intracellular concentration
typically higher than the extracellular concentration? - ✔✔potassium
ions
At the plasma membrane, which of the following phospholipids is found
exclusively on the intracellular [SHOULD HAVE SAID "extracellular"]
leaflet? - ✔✔glycolipids
What is the structural basis for the ion selectivity of the voltage gated
potassium channel? - ✔✔a series of carbonyl oxygen atoms along the
selectivity channel
During the transport cycle of the calcium ATPase, which of the
following events causes the conformation change that enables
transport of 2 calcium ions out of the cytosol? - ✔✔phosphorylation of
an aspartate residue
, During the transport cycle for the sodium-potassium ATPase, which
event occurs immediately after dephosphorylation of the critical
aspartate residue? - ✔✔transport of 2 potassium ions from the
extracellular compartment to the cytosolic compartment
Which of the following events is responsible for the repolarization
phase of the action potential?
a) opening of voltage gated sodium channels
b) opening of voltage gated potassium channels
c) inactivation of voltage gated sodium channels
d) two of the above
e) all of the above - ✔✔two of the above
5 Essential Characteristics of All Living Cells? - ✔✔Capable of protein
synthesis
Capable of autonomous replication
COMPLETE QUESTIONS AND 100%
CORRECT ANSWERS { GRADED A+}
How is the asymmetrical distribution of phospholipids across the
plasma membrane created? - ✔✔ABC transporters called flippases
move them between the cytosolic and luminal leaflets of the ER
membrane
Which of the following is FALSE regarding bacteriorhodopsin? - ✔✔it
pumps protons into of the cytosol
Which of following modifications would result in increased membrane
fluidity? - ✔✔increased amount of unsaturation of fatty acid tails
,How is phosphatidylserine different from all other phospholipids? -
✔✔it is negatively charged at neutral pH
Which of the following proteins transports sodium ions against their
concentration gradient? - ✔✔sodium-potassium ATPase
Which of the following organelles is responsible for the synthesis of
new membrane for components of the endomembrane system? -
✔✔endoplasmic reticulum
Which of the following proteins is/are NOT (an) ABC transporter(s)? -
✔✔calcium ATPase
In epithelial cells, how is glucose transported across the apical
membrane? - ✔✔sodium-glucose symporter
The resting potential of the plasma membrane of an excitable cell is
primarily due to the selective permeability of the membrane to which
of the following ions? - ✔✔potassium ions
,True or False? "Only the extracellular domains of membrane
glycoproteins can be glycosylated." - ✔✔True
For which of the following ions is the intracellular concentration
typically higher than the extracellular concentration? - ✔✔potassium
ions
At the plasma membrane, which of the following phospholipids is found
exclusively on the intracellular [SHOULD HAVE SAID "extracellular"]
leaflet? - ✔✔glycolipids
What is the structural basis for the ion selectivity of the voltage gated
potassium channel? - ✔✔a series of carbonyl oxygen atoms along the
selectivity channel
During the transport cycle of the calcium ATPase, which of the
following events causes the conformation change that enables
transport of 2 calcium ions out of the cytosol? - ✔✔phosphorylation of
an aspartate residue
, During the transport cycle for the sodium-potassium ATPase, which
event occurs immediately after dephosphorylation of the critical
aspartate residue? - ✔✔transport of 2 potassium ions from the
extracellular compartment to the cytosolic compartment
Which of the following events is responsible for the repolarization
phase of the action potential?
a) opening of voltage gated sodium channels
b) opening of voltage gated potassium channels
c) inactivation of voltage gated sodium channels
d) two of the above
e) all of the above - ✔✔two of the above
5 Essential Characteristics of All Living Cells? - ✔✔Capable of protein
synthesis
Capable of autonomous replication
