A defense cell engulfing a bacterium illustrates:

A defense cell engulfing a bacterium illustrates
 A) pinocytosis.
  B) receptor-mediated exocytosis.
  C) exocytosis.
  D) phagocytosis.
  E) receptor-mediated endocytosis.

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(Question 2) Receptor-mediated endocytosis
 A) is a type of secretion.
  B) imports target molecules after they bind to membrane proteins.
  C) does not require energy from the cell.
  D) can only move a substance down its concentration gradient.
  E) imports extracellular fluid, including all of its dissolved molecules.

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(Question 3) Endocytosis is a
 A) method for transporting substances into the cell.
  B) method for metabolizing within the cytosol.
  C) form of anabolism.
  D) viral infection.
  E) method for packaging secretions.

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(Question 4) The intake of materials from the extracellular fluid using vesicles is called
 A) osmosis.
  B) exocytosis.
  C) facilitated transport.
  D) endocytosis.
  E) an ion exchange pump.

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(Question 5) All of the following membrane transport mechanisms are passive processes except
 A) diffusion.
  B) facilitated diffusion.
  C) vesicular transport.
  D) osmosis.
  E) movement of water.

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(Question 6) In order to maintain cellular homeostasis, one abundant type of exchange pump ejects ________ ions from the cell and imports ________ ions.
 A) potassium; calcium
  B) sodium; calcium
  C) potassium; sodium
  D) sodium; potassium
  E) calcium; sodium

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(Question 7) An extracellular cation whose concentration gradient drives the secondary active transport of many different solutes is
 A) sodium.
  B) calcium.
  C) potassium.
  D) chloride.
  E) glucose.

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(Question 8) Secondary active transport
 A) is not carried out by membrane proteins.
  B) is not directly linked to the hydrolysis of ATP.
  C) does not link the pumping of one substance to the concentration gradient of another.
  D) does not require the cell to invest energy, either directly or indirectly.
  E) cannot move a substance against its concentration gradient.

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(Question 9) 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.

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(Question 10) Membrane-bound proteins that use metabolic energy to move ions across the plasma membrane are called ________ pumps.
 A) channel
  B) receptor
  C) active
  D) motor
  E) ion