32. Facilitated diffusion differs from ordinary diffusion in that a. facilitated diffusion expends no ATP b. facilitated diffusion moves molecules from an area of their higher concentration to their lower concentration c. the rate of molecular movement is limited by the number of available carrier molecules d. facilitated diffusion never eliminates the concentration gradient e. the rate of molecular movement is not limited by the number of available carrier molecules 33. A process that requires cellular energy to move a substance against its concentration gradient is called a. active transport b. passive transport C. facilitated transport d. osmosis e. diffusion 34. Tubulin is to microtubules as actin is to a. ribosomes b. microfilaments C. intermediate filaments d. flagella e. microvilli Which of the following cytoskeleton components are responsible for the movement of chromosomes during cell division? a. microfilaments b. intermediate filaments c. thick filaments d. microtubules e. basal bodies 36. The components of ribosomes are formed by a. the endoplasmic reticulum b. Golgi complexes C. lysosomes d. mitochondria e. nucleoli 35
