Questions and Answers 100% Pass
Actin filaments:
a) have a diameter of 7 nm and contain 375 amino acids.
b) are composed of 2 subunits each of molecular weight of 42 kDa.
c) have a diameter of 7 nm and contain 450 amino acids.
d) have no polarity.
e) have GTP in each of the monomers.
f) The correct answer is not listed. - ✔✔f) The correct answer is not listed.
Actin filaments will
a) undergo treadmilling in a test tube.
b) undergo treadmilling in a living cell.
c) never reach equilibrium.
d) two of the above.
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,e) none of the above. - ✔✔d) two of the above.
The number of amino acids in an actin monomer is:
a) 375
b) 450
c) 460 -780
d) 750
f) none of the above - ✔✔a) 375
Hydrolysis of ATP to ADP:
a) helps identify the assembly vs the disassembly end
b) is used in dynamic instability
c) has a role when the actin filament is in chemical equilibrium with the actin filament
monomers
d) is important for the nucleation site
e) none of the above - ✔✔a) helps identify the assembly vs the disassembly end
Actin filaments associate with a nucleotide triphosphate.
a) True
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, b) False - ✔✔a) True
Treadmilling of actin filaments only occurs in a test tube.
a) True
b) False - ✔✔b) False
Preassembled nucleation sites in a living cell are equivalent to the intracellular
preference for actin filaments
a) True
b) False - ✔✔a) True
Intracellular preference for actin filaments :
a) is a way to look a the geography of the cell and the role of the nucleus.
b) is a way to look at the geography of the cell and show where the role of actin
filaments is important.
c) explain how actin gets into the nucleus.
d) explain how the Golgi Apparatus forms.
e) two of the above. - ✔✔b) is a way to look at the geography of the cell and show
where the role of actin filaments is important.
The ability of actin filaments to disassemble into small monomers:
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