Lecture 16

Question 1

Which of the following functions is NOT associated with the cytoskeleton in eukaryotic cells?

a. the contraction of muscle cells in animals
b. maintaining the position of the nucleus in the cell
c. determining the shape of animal cells
d. the beating of cilia or flagella
e. Movement of RNA molecules from the nucleus to the cytoplasm

Answer 1

e. Movement of RNA molecules from the nucleus to the cytoplasm

Question 2

Researchers tried to explain how vesicular transport occurs in cells by attempting to assemble the transport components. They set up microtubular tracks along which vesicles could be transported, and they added vesicles and ATP (because they knew the transport process requires energy). Yet, when they put everything together, there was no movement or transport of vesicles. What were they missing?

a. an axon
b. endoplasmic reticulum
c. motor proteins
d. contractile microfilaments

Answer 2

c. motor proteins

Question 3

Cilia and flagella bend because of _____.

a. a motor protein called radial spokes
b. the quick inward movements of water by osmosis.
c. a motor protein called dynein
d. conformational changes in ATP that thrust microtubules laterally

Answer 3

c. a motor protein called dynein