1. Directional transport within the endomembrane system (anterograde vc. retrograde transport) is mediated by which of the following.
a. Kinesin and dynein motors on microtubules
b. Myosin motors actin filaments
c. Sliding of microtubules against each other using dynein motors.
d. Desmosomal movement along intermediate filaments.
2. Dynamic assembly and disassembly of a cytoplasmic microtubule in a cell occurs primarily at the MT plus end, because the minus end is usually anchored to?
a. a GTP-cap
b. a centromere
c. a microtubule organizing center
d. a mitochondrial outer membrane
e. the plasma membrane
Answer:
1. (a) Kinesin and dynein motors on microtubules
Explanation:
Kinesin is involved in ATP-dependent transport toward the plus
ends of MTs, called anterograde transport.
Dynein moves particles (cargo) in the opposite direction, called
retrograde transport.
2. (c) a microtubule organizing center
Explanation:
The microtubules in most cells extend outward from a microtubule-organizing center, in which the minus ends of microtubules are anchored. In animal cells, the major microtubule-organizing center is the centrosome.
1. Directional transport within the endomembrane system (anterograde vc. retrograde transport) is mediated by which of...
please answer all that you can 1. You have genetically engineered green fluorescent protein (GFP) containing a KDEL sequence (GFP-KDEL). When GFP-KDEL is expressed in normal human fibroblasts and examined using fluorescence microscopy, the fluorescence appears diffuse across the cytoplasm. How would you explain this observations given that KDEL is supposed to be an ER-specific sorting sequence? A. This engineered GFP would not have a hydrophobic signal sequence to get it into the RER in the first place. B. The...