Download The table below shows the chemical characteristics of four

PROCTOR VERSION
2.9 D: Cell Transport Quiz
1.
The table below shows the chemical characteristics of four substances.
Based on the data, which substance will diffuse through a cell membrane most easily?
(A) Substance 1
Distractor Rationale:
This answer suggests the student may understand that small size is important for diffusion
through membranes, but does not understand that charged ions do not easily pass
through membrane lipids because the phospholipid bilayer is hydrophobic.
(B) Substance 2
Distractor Rationale:
This answer suggests the student may understand that small size is important for diffusion
through membranes, but does not understand that although cell membranes have both
polar and non-polar properties, polar molecules do not easily pass through the non-polar
lipid region of the membrane.
(C) Substance 3
Rationale:
This answer suggests the student understands that small size is an important characteristic
that allows substances to diffuse through plasma membranes, and that the molecule’s nonpolarity is an important characteristic because of the non-polarity of the lipid tails of
phospholipids.
(D) Substance 4
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PROCTOR VERSION
2.9 D: Cell Transport Quiz
Distractor Rationale:
This answer suggests the student may understand that non-polarity is an important
characteristic for being able to diffuse through membranes, but does not understand that
large molecules do not easily pass through the lipid region of the membrane due to their
size.
Aligned to: LO 2.9 CA 2.9: Represent & Model Matter Exchange
2.
In a person with cystic fibrosis, epithelial cells lining the lungs and digestive system lack a
membrane protein needed to remove excess chloride ions from the cell. Which statement best
explains how this disorder affects an epithelial cell?
(A) The low concentration of chloride ions inside the cell causes water to move from the cell to
the cytoplasm, resulting in the cell becoming dehydrated.
Distractor Rationale:
This answer suggests the student may understand that a low concentration of chloride ions
inside the cell would cause water to move out of the cell, but does not understand that the
ion concentration inside the cell is high, and that water will flow into the cell and cause it to
swell and possibly burst.
(B) The high concentration of chloride ions inside the cell causes sodium ions to diffuse into the
cell, resulting in the formation of sodium chloride crystals.
Distractor Rationale:
This answer suggests the student may understand that substances can diffuse across the
plasma membrane and that the chloride ion concentration inside the cell is high, but does
not understand that sodium ions do not move across the plasma membrane through simple
diffusion, and that water would move into the cell and cause the cell to swell.
(C) The low concentration of chloride ions inside the cell causes sodium ions to diffuse into the
cell, resulting in shrinking and shriveling of the cell.
Distractor Rationale:
This answer suggests the student may understand that a low concentration of chloride ions
inside the cell relative to the concentration outside the cell will cause the cell to shrink and
shrivel, but does not understand that only water moves into and out of the cell, that the
concentration of chloride ions is higher inside the cell relative to outside, and that the higher
ion concentration causes water to move into the cell and causes the cell to swell.
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PROCTOR VERSION
2.9 D: Cell Transport Quiz
(D) The high concentration of chloride ions inside the cell causes water to diffuse into the cell,
resulting in swelling and bursting of the cell.
Rationale:
This answer suggests the student understands that a high chloride concentration inside the
cell causes water to diffuse across the plasma membrane into the cell, which causes the cell
to swell.
Aligned to: LO 2.9 CA 2.9: Represent & Model Matter Exchange
3.
The diagram below shows the movement of particles across a cell membrane.
Which statement describes the process most likely represented by the diagram?
(A) Oxygen is moving into a cell via simple diffusion.
Rationale:
This answer suggests the student understands that oxygen can pass through the cell
membrane by simple diffusion because oxygen is a small, nonpolar molecule.
(B) Sodium ions are moving into a cell via osmosis.
Distractor Rationale:
This answer suggests the student may understand that water moves across a cell
membrane via osmosis, but does not understand that osmosis involves only the movement
of water molecules, and not ions.
(C) Glucose is being moved into a cell via active transport.
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PROCTOR VERSION
2.9 D: Cell Transport Quiz
Distractor Rationale:
This answer suggests the student may understand that glucose can move across a cell
membrane via active transport, but does not understand that carrier proteins are involved
and that the movement is usually against a concentration gradient.
(D) Proteins are being moved into a cell via endocytosis.
Distractor Rationale:
This answer suggests the student understands that proteins could move across a cell
membrane via endocytosis, but does not understand that endocytosis involves the
membrane wrapping around the molecule.
Aligned to: LO 2.9 CA 2.9: Represent & Model Matter Exchange
4.
The diagram below shows the movement of ions through the phospholipid bilayer of a cell.
Based on the diagram, which statement best explains the movement of the ions through the
phospholipid bilayer?
(A) The ions can diffuse across the phospholipid bilayer because the ions are moving against
the osmotic potential.
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PROCTOR VERSION
2.9 D: Cell Transport Quiz
Distractor Rationale:
This answer suggests the student may understand that diffusion is the movement of ions
from high concentration to low concentration, but does not understand that osmotic
potential refers to the movement of water and not the movement of ions.
(B) The ions are transported across the phospholipid bilayer because the ions are moving
against the concentration gradient.
Distractor Rationale:
This answer suggests the student may understand that the ions must be transported across
the phospholipid bilayer, but does not understand that the ions must be transported
because they are charged, and that the ions are not moving against a concentration
gradient.
(C) The ions can diffuse across the phospholipid bilayer because the ions are nonpolar.
Distractor Rationale:
This answer suggests the student may understand that diffusion is the movement of a
substance from high concentration to low concentration, but does not understand that an
ion is charged and requires a channel protein to move across the phospholipid bilayer.
(D) The ions are transported across the phospholipid bilayer because the ions are charged.
Rationale:
This answer suggests the student understands that the ions are moving from an area of
high concentration to an area of low concentration via facilitated diffusion through a protein
channel because they are charged.
Aligned to: LO 2.9 CA 2.9: Represent & Model Matter Exchange
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