111) Which of these transport processes always requires metabolic energy? A) diffusion B) carrier-mediated transport C) vesicular transport D) freely permeable E) impermeable 112) A membrane transport process is found experimentally to have a saturation limit. Which of the following is a possible property of the process? A) energy-dependent B) carrier-mediated C) cotransport D) active transport E) All of the answers are correct. 113) Assume that the transport of a particular amino acid across the plasmalemma is observed (1) to occur only down its concentration gradient and (2) to slow when a similar amino acid is added to the extracellular fluid. The movement of the amino acid through the membrane is most likely by A) osmosis. B) diffusion. C) facilitated diffusion. D) active transport. E) pinocytosis. 114) Which of the following about a cell’s resting transmembrane potential is false? A) inside slightly more positive than outside B) inside slightly more negative than outside C) depends on separation of + and – charges D) represents potential energy E) controls muscular contraction and nervous signaling 115) The potential difference across the cell membrane is due to the separation of A) carbohydrate molecules. B) water molecules. C) cations and anions. D) acids and bases. E) phospholipids and proteins. 116) Changes in the transmembrane potential of a cell are involved in A) movement. B) thought. C) glandular secretion. D) nerve cell communication. E) All of the answers are correct. 117) In a series of measurements of resting transmembrane potentials, the following values were recorded. Which one is likeliest to be an error? A) -10 mV B) -20 mV C) -40 mV D) -70 mV E) +100 mV 118) If a cell lacked the enzyme DNA polymerase, it could not A) form protein. B) form complementary sequences of DNA. C) link segments of DNA together. D) form spindle fibers. E) form a new nuclear membrane during telophase. 119) When is DNA replicated? A) interphase B) anaphase C) metaphase D) telophase E) interkinesis 120) The stage in a cell’s life cycle in which the cell performs its normal functions and prepares for division is called A) prophase. B) metaphase. C) interphase. D) telophase. E) anaphase.