Cytoskeleton Ch. 10 Latest Update | Graded A+

Cytoskeleton Ch. 10 Latest Update | Graded A+ **Question 1: What are microfilaments composed of and how are they arranged?** - **(a)** Keratin proteins; a single-strand - **(b)** Actin subunits; a thin double-helix - **(c)** Tubulin dimers; a hollow tube - **(d)** Collagen fibers; a triple-helix (b) Actin subunits; a thin double-helix **Question 2: What is one of the primary functions of microfilaments in a cell?** - **(a)** Transmit genetic information - **(b)** Maintain cell size and shape - **(c)** Store energy - **(d)** Transport proteins across the membrane (b) Maintain cell size and shape **Question 3: How can microfilaments facilitate cell movement?** - **(a)** By stabilizing cell junctions - **(b)** Through dynamic growing and shrinking at their ends - **(c)** By forming rigid structures - **(d)** By providing a scaffold for enzyme activity (b) Through dynamic growing and shrinking at their ends **Question 4: What process would likely lead to the development of a microvillus on an intestinal epithelial cell?** - **(a)** Random assembly of microtubules - **(b)** Plus (+) end growth of microfilaments at the tip of the microvillus with no shrinkage at the minus (−) end - **(c)** Symmetrical assembly of intermediate filaments - **(d)** Degradation of existing microfilaments (b) Plus (+) end growth of microfilaments at the tip of the microvillus with no shrinkage at the minus (−) end **Question 5: How do microfilaments contribute to the structure and function of red blood cells?** - **(a)** By regulating ion exchange - **(b)** By maintaining the biconcave shape to maximize gas exchange - **(c)** By synthesizing hemoglobin - **(d)** By providing a rigid structure to prevent deformation (b) By maintaining the biconcave shape to