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STRUCTURE AND FUNCTION OF THE CELL
Chapter 3: Structure and Function of the Cell
Multiple Choice
1. The structural and functional unit of all living organisms is the
A) ribosome.
B) cell.
C) organ.
D) organelle.
E) plasma membrane.
Answer: b
Level: 1
2. Which of the following could be used to study general features of cells?
A) a magnifying glass
B) scanning electron microscope
C) transmission electron microscope
D) binoculars
E) light microscope
Answer: e
Level: 1
3. In order to study in detail, the anatomy of internal cell parts, it would be best to use
A) x-rays.
B) flashlights.
C) a transmission electron microscope (TEM).
D) tissue cultures.
E) a scanning electron microscope (SEM).
Answer: c
Level: 1
4. The plasma membrane
A) separates the nucleus from the rest of the cell.
B) is a rigid protein membrane.
C) is not permeable.
D) has a single layer of phospholipids.
E) regulates movement of materials into and out of the cell.
Answer: e
Level: 1
5. The environment outside the plasma membrane is most appropriately referred to as
A) intracellular.
B) extracellular.
C) multicellular.
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STRUCTURE AND FUNCTION OF THE CELL
D) centrocellular.
E) none of the above.
Answer: b
Level: 1
6. The fluid-mosaic model of the plasma membrane suggests that
A) cholesterol forms the outermost layer of the membrane.
B) proteins form a "liquid" sea in the membrane.
C) phospholipids form a single lipid layer in the center of the membrane.
D) the membrane is neither rigid nor static in structure.
E) proteins are not a part of the membrane.
Answer: d
Level: 1
7. According to the most current model of the plasma membrane
A) cholesterol forms the innermost layer of the membrane
B) proteins are free to move about with a double layer of phospholipids
C) phospholipids and cholesterol form a single lipid bilayer
D) the membrane is a rigid unchanging structure
E) the membrane is impermeable to all other molecules.
Answer: b
Level: 1
8. Which of the following activities is a function of the plasma membrane?
A) digestion of unneeded cell organelles
B) recognition of bacterial cells by the immune system
C) transport of products from the nucleus to the endoplasmic reticulum
D) cell metabolism
E) detoxification
Answer: b
Level: 2
9. Plasma membrane phospholipids
A) have polar (charged) tails.
B) are arranged in a single layer.
C) have tails that face the exterior of the membrane.
D) are 95% cholesterol.
E) have a hydrophilic head and hydrophobic tails.
Answer: e
Level: 1
10. Which of the following is correctly matched with its function?
A) channel proteins - are part of an intercellular communication system
B) marker molecules - are primarily steroids
C) receptor molecules - attach to ligand molecules.
D) peripheral proteins - penetrate the lipid bilayer from one surface to the other.
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STRUCTURE AND FUNCTION OF THE CELL
E) nongated ion channels - are always closed.
Answer: c
Level: 1
11. In general, water-soluble molecules diffuse through the ; and lipid-soluble
molecules diffuse through the .
A) protein channels; protein channels
B) protein channels; bilipid layer
C) bilipid layer; protein channels
D) bilipid layer; bilipid layer
E) none of the above
Answer: b
Level: 2
12. Cell membrane phospholipids
A) have nonpolar fatty acid tails.
B) form a bilayer.
C) have polar phosphate heads.
D) create a selectively permeable barrier.
E) all of the above
Answer: e
Level: 1
13. When a sperm cell comes into contact with an egg cell, there is a change in the electrical
charge across the plasma membrane and various channel proteins close. These channels would
be called
A) open-gated channels.
B) voltage-gated channels.
C) chemical-gated channels.
D) ligand-gated channels.
E) nongated ion channels.
Answer: b
Level: 2
14. Communication between cells occurs when chemical messengers from one cell bind to
on another cell.
A) channel proteins
B) receptor molecules
C) marker molecules
D) second messengers
E) integrins.
Answer: b
Level: 1
15. Channel proteins
A) are binding sites for other molecules.
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STRUCTURE AND FUNCTION OF THE CELL
B) utilize the G protein complex to function.
C) are found only on endoplasmic reticulum.
D) allow cells to recognize one another.
E) provide a "door" through which extracellular molecules can enter the cell
Answer: e
Level: 1
16. Molecules that serve as chemical signals in cell to cell communication are called
A) isotopes.
B) ligands.
C) responders.
D) communicators.
E) membrane potentials.
Answer: b
Level: 1
17. Cells that respond to ligands
A) possess receptor sites for specific ligands.
B) generally produce the ligands.
C) have lysosomes that destroy the ligands.
D) are using electrical signals in cellualar communication.
E) are not functional.
Answer: a
Level: 1
18. Membrane-bound receptors
A) are small, lipid soluble molecules.
B) have their receptor sites on the outer surface of the plasma membrane.
C) can interact with DNA in the nucleus.
D) do not exhibit specificity.
E) have no effect on the cell.
Answer: b
Level: 1
19. Consider the following events and choose the one that occurs last.
A) Acetylcholine is released from neurons.
B) Acetylcholine diffuses across the synapse to the receptor.
C) Na+ ion channels in the plasma membrane are opened.
D) Acetylcholine binds to membrane-bound receptors on skeletal muscle cells
E) Na+ ions diffuse into skeletal muscle cells.
Answer: e
Level: 2
20. G proteins are found associated with the
A) nucleus.
B) cytoplasm.
NSCI/280 280/
STRUCTURE AND FUNCTION OF THE CELL
Chapter 3: Structure and Function of the Cell
Multiple Choice
1. The structural and functional unit of all living organisms is the
A) ribosome.
B) cell.
C) organ.
D) organelle.
E) plasma membrane.
Answer: b
Level: 1
2. Which of the following could be used to study general features of cells?
A) a magnifying glass
B) scanning electron microscope
C) transmission electron microscope
D) binoculars
E) light microscope
Answer: e
Level: 1
3. In order to study in detail, the anatomy of internal cell parts, it would be best to use
A) x-rays.
B) flashlights.
C) a transmission electron microscope (TEM).
D) tissue cultures.
E) a scanning electron microscope (SEM).
Answer: c
Level: 1
4. The plasma membrane
A) separates the nucleus from the rest of the cell.
B) is a rigid protein membrane.
C) is not permeable.
D) has a single layer of phospholipids.
E) regulates movement of materials into and out of the cell.
Answer: e
Level: 1
5. The environment outside the plasma membrane is most appropriately referred to as
A) intracellular.
B) extracellular.
C) multicellular.
,NSCI/280
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STRUCTURE AND FUNCTION OF THE CELL
D) centrocellular.
E) none of the above.
Answer: b
Level: 1
6. The fluid-mosaic model of the plasma membrane suggests that
A) cholesterol forms the outermost layer of the membrane.
B) proteins form a "liquid" sea in the membrane.
C) phospholipids form a single lipid layer in the center of the membrane.
D) the membrane is neither rigid nor static in structure.
E) proteins are not a part of the membrane.
Answer: d
Level: 1
7. According to the most current model of the plasma membrane
A) cholesterol forms the innermost layer of the membrane
B) proteins are free to move about with a double layer of phospholipids
C) phospholipids and cholesterol form a single lipid bilayer
D) the membrane is a rigid unchanging structure
E) the membrane is impermeable to all other molecules.
Answer: b
Level: 1
8. Which of the following activities is a function of the plasma membrane?
A) digestion of unneeded cell organelles
B) recognition of bacterial cells by the immune system
C) transport of products from the nucleus to the endoplasmic reticulum
D) cell metabolism
E) detoxification
Answer: b
Level: 2
9. Plasma membrane phospholipids
A) have polar (charged) tails.
B) are arranged in a single layer.
C) have tails that face the exterior of the membrane.
D) are 95% cholesterol.
E) have a hydrophilic head and hydrophobic tails.
Answer: e
Level: 1
10. Which of the following is correctly matched with its function?
A) channel proteins - are part of an intercellular communication system
B) marker molecules - are primarily steroids
C) receptor molecules - attach to ligand molecules.
D) peripheral proteins - penetrate the lipid bilayer from one surface to the other.
,NSCI/280
NSCI/280 280/
STRUCTURE AND FUNCTION OF THE CELL
E) nongated ion channels - are always closed.
Answer: c
Level: 1
11. In general, water-soluble molecules diffuse through the ; and lipid-soluble
molecules diffuse through the .
A) protein channels; protein channels
B) protein channels; bilipid layer
C) bilipid layer; protein channels
D) bilipid layer; bilipid layer
E) none of the above
Answer: b
Level: 2
12. Cell membrane phospholipids
A) have nonpolar fatty acid tails.
B) form a bilayer.
C) have polar phosphate heads.
D) create a selectively permeable barrier.
E) all of the above
Answer: e
Level: 1
13. When a sperm cell comes into contact with an egg cell, there is a change in the electrical
charge across the plasma membrane and various channel proteins close. These channels would
be called
A) open-gated channels.
B) voltage-gated channels.
C) chemical-gated channels.
D) ligand-gated channels.
E) nongated ion channels.
Answer: b
Level: 2
14. Communication between cells occurs when chemical messengers from one cell bind to
on another cell.
A) channel proteins
B) receptor molecules
C) marker molecules
D) second messengers
E) integrins.
Answer: b
Level: 1
15. Channel proteins
A) are binding sites for other molecules.
, NSCI/280
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STRUCTURE AND FUNCTION OF THE CELL
B) utilize the G protein complex to function.
C) are found only on endoplasmic reticulum.
D) allow cells to recognize one another.
E) provide a "door" through which extracellular molecules can enter the cell
Answer: e
Level: 1
16. Molecules that serve as chemical signals in cell to cell communication are called
A) isotopes.
B) ligands.
C) responders.
D) communicators.
E) membrane potentials.
Answer: b
Level: 1
17. Cells that respond to ligands
A) possess receptor sites for specific ligands.
B) generally produce the ligands.
C) have lysosomes that destroy the ligands.
D) are using electrical signals in cellualar communication.
E) are not functional.
Answer: a
Level: 1
18. Membrane-bound receptors
A) are small, lipid soluble molecules.
B) have their receptor sites on the outer surface of the plasma membrane.
C) can interact with DNA in the nucleus.
D) do not exhibit specificity.
E) have no effect on the cell.
Answer: b
Level: 1
19. Consider the following events and choose the one that occurs last.
A) Acetylcholine is released from neurons.
B) Acetylcholine diffuses across the synapse to the receptor.
C) Na+ ion channels in the plasma membrane are opened.
D) Acetylcholine binds to membrane-bound receptors on skeletal muscle cells
E) Na+ ions diffuse into skeletal muscle cells.
Answer: e
Level: 2
20. G proteins are found associated with the
A) nucleus.
B) cytoplasm.
