4 Written questions
4 Matching questions
- 32) Which of the following statements correctly describes the normal tonicity conditions for typical plant and animal cells?
A) The animal cell is in a hypotonic solution, and the plant cell is in an isotonic solution.
B) The animal cell is in an isotonic solution, and the plant cell is in a hypertonic solution.
C) The animal cell is in a hypertonic solution, and the plant cell is in an isotonic solution.
D) The animal cell is in an isotonic solution, and the plant cell is in a hypotonic solution.
E) The animal cell is in a hypertonic solution, and the plant cell is in a hypotonic solution.
- 36) The phosphate transport system in bacteria imports phosphate into the cell even when the concentration of phosphate outside the cell is much lower than the cytoplasmic phosphate concentration. Phosphate import depends on a pH gradient across the membrane-more acidic outside the cell than inside the cell. Phosphate transport is an example of
A) passive diffusion.
B) facilitated diffusion.
C) active transport.
- 19) In a paramecium, cell surface integral membrane proteins are synthesized
A) in the cytoplasm by free ribosomes.
B) by ribosomes in the nucleus.
C) by ribosomes bound to the rough endoplasmic reticulum.
D) by ribosomes in the Golgi vesicles.
E) by ribosomes bound to the inner surface of the plasma membrane.
- 25) Which of the following is a characteristic feature of a carrier protein in a plasma membrane?
A) It is a peripheral membrane protein.
B) It exhibits a specificity for a particular type of molecule.
C) It requires the expenditure of cellular energy to function.
D) It works against diffusion.
E) It has few, if any, hydrophobic amino acids.
- a e
- b d
- c c
- d b
5 Multiple choice questions
5 True/False questions
35) Which of the following membrane activities require energy from ATP hydrolysis?
A) facilitated diffusion of chloride ions across the membrane through a chloride channel
B) movement of water into a cell
C) Na+ ions moving out of a mammalian cell bathed in physiological saline
D) movement of glucose molecules into a bacterial cell from a medium containing a higher concentration of glucose than inside the cell
E) movement of carbon dioxide out of a paramecium → c
53) A bacterium engulfed by a white blood cell through phagocytosis will be digested by enzymes contained in
C) Golgi vesicles.
E) secretory vesicles. → b
45) The sodium-potassium pump in animal cells requires cytoplasmic ATP to pump ions across the plasma membrane. When the proteins of the pump are first synthesized in the rough ER, what side of the ER membrane will the ATP binding site be on?
A) It will be on the cytoplasmic side of the ER.
B) It will be on the side facing the interior of the ER.
C) It could be facing in either direction because proteins are properly reoriented in the Golgi apparatus.
D) It doesn't matter, because the pump is not active in the ER. → a
14) An animal cell lacking oligosaccharides on the external surface of its plasma membrane would likely be impaired in which function?
A) transporting ions against an electrochemical gradient
B) cell-cell recognition
C) maintaining fluidity of the phospholipid bilayer
D) attaching to the cytoskeleton
E) establishing the diffusion barrier to charged molecules → a
41) Which of the following is most likely true of a protein that cotransports glucose and sodium ions into the intestinal cells of an animal?
A) The sodium ions are moving down their electrochemical gradient while glucose is moving up.
B) Glucose entering the cell along its concentration gradient provides energy for uptake of sodium ions against the electrochemical gradient.
C) Sodium ions can move down their electrochemical gradient through the cotransporter whether or not glucose is present outside the cell.
D) The cotransporter can also transport potassium ions.
E) A substance that blocks sodium ions from binding to the cotransport protein will also block the transport of glucose. → e