Name: KEY Block: Date:
Biology 12 - Cell Membrane & Transport – Review Worksheet
⇒ Part A: Definitions: Define the following terms, IN YOUR OWN WORDS, IN AS FEW WORDS AS CLARITY ALLOWS.
phospholipid and protein covering of every cell, controls what goes in and out of each
i. cell membrane cell
movement of molecules from region of greater concentration to region of lesser
ii. diffusion concentration.
the difference in concentration between two regions
iii. concentration gradient
the solid that is dissolved in a solution
iv. solute
the liquid that dissolves the solute in a solution
v. solvent
the pressure of water moving across membranes caused by a concentration gradient.
vi. osmotic pressure
solution that has same concentration of solute as the cells it surrounds
vii. isotonic solution
solution that has greater concentration of solute as the cells it surrounds. Will cause
viii. hypertonic solution cell to shrink
solution that has lesser concentration of solute as the cells it surrounds. Will cause
ix. hypotonic solution cells to burst
shrinking of a plant cell (wilting) due to being place in a hypertonic solution.
x. plasmolysis
hydrostatic pressure due to a plant cell being placed in hypotonic solution. Is
xi. turgor pressure pressure on inside of plant cell against the cell wall.
Carrier-mediated transport that works with the conc. gradient and requires no energy.
xii. facilitated transport
shrinking of animal cells placed in hypertonic solutions.
xiii. crenation
Carrier-mediated transport that works against the conc. gradient and requires energy.
xiv. active transport
Cells bringing in materials by forming vesicle around substance outside the cell with
xv. endocytosis the cell membrane.
endocytosis of large particles (large enough to be seen with light microscope)
xvi. phagocytosis
“cell drinking” Endocytosis of small particles (small enough that an electron
xvii. pinocytosis microscope is needed)
opposite of endocytosis. Vesicle inside cell fuses with cell membrane, depositing
xviii. exocytosis contents on the outside.
carbohydrate attached to phospholipid on cell membrane. Often serves in cell
xix. glycolipid identification and communication.
Current model of membrane structure. A phospholipid fluid sea is embedded with a
xx. Fluid Mosaic Model wide variety (“mosaic”) of protein molecules.
PART B - SHORT ANSWERS
1. Diffusion is the movement of molecules from the area of greater concentration to the area of lesser
concentration.
2. Osmosis is the movement of water across a selectively permeable membrane.
3. A cell is isotonic to a solution of 0.01% sugar.
a. What concentration would by hypertonic? >0.01%
b. What concentration would be hypotonic? <0.01%
4. a) What happens to an animal cell in a hypotonic solution? it swells and bursts
b) What happens to an animal cell in a hypertonic solution? It loses water to medium -- shrivels up.
5. Turgor pressure is best exemplified by placing a plant cell in a hypotonic solution.
6. Give an example:
a. of diffusion in the body the movement of O2 from the air sacs into the blood
b. of facilitated transport some sugars enter the cell more quickly than others
c. of active transport the concentration ([]) of Na is greater outside a cell, the [] of K is greater inside a cell
7. List 3 ways in which active transport differs from the process of diffusion across a cell membrane.
i. goes from area of less[] to area of greater
ii. requires carrier protein
iii. requires expenditure of energy
Raycroft 4.5 Worksheet - Cell Membrane - Review Worksheet Key - Page 1
Biology 12 - Cell Membrane & Transport – Review Worksheet
⇒ Part A: Definitions: Define the following terms, IN YOUR OWN WORDS, IN AS FEW WORDS AS CLARITY ALLOWS.
phospholipid and protein covering of every cell, controls what goes in and out of each
i. cell membrane cell
movement of molecules from region of greater concentration to region of lesser
ii. diffusion concentration.
the difference in concentration between two regions
iii. concentration gradient
the solid that is dissolved in a solution
iv. solute
the liquid that dissolves the solute in a solution
v. solvent
the pressure of water moving across membranes caused by a concentration gradient.
vi. osmotic pressure
solution that has same concentration of solute as the cells it surrounds
vii. isotonic solution
solution that has greater concentration of solute as the cells it surrounds. Will cause
viii. hypertonic solution cell to shrink
solution that has lesser concentration of solute as the cells it surrounds. Will cause
ix. hypotonic solution cells to burst
shrinking of a plant cell (wilting) due to being place in a hypertonic solution.
x. plasmolysis
hydrostatic pressure due to a plant cell being placed in hypotonic solution. Is
xi. turgor pressure pressure on inside of plant cell against the cell wall.
Carrier-mediated transport that works with the conc. gradient and requires no energy.
xii. facilitated transport
shrinking of animal cells placed in hypertonic solutions.
xiii. crenation
Carrier-mediated transport that works against the conc. gradient and requires energy.
xiv. active transport
Cells bringing in materials by forming vesicle around substance outside the cell with
xv. endocytosis the cell membrane.
endocytosis of large particles (large enough to be seen with light microscope)
xvi. phagocytosis
“cell drinking” Endocytosis of small particles (small enough that an electron
xvii. pinocytosis microscope is needed)
opposite of endocytosis. Vesicle inside cell fuses with cell membrane, depositing
xviii. exocytosis contents on the outside.
carbohydrate attached to phospholipid on cell membrane. Often serves in cell
xix. glycolipid identification and communication.
Current model of membrane structure. A phospholipid fluid sea is embedded with a
xx. Fluid Mosaic Model wide variety (“mosaic”) of protein molecules.
PART B - SHORT ANSWERS
1. Diffusion is the movement of molecules from the area of greater concentration to the area of lesser
concentration.
2. Osmosis is the movement of water across a selectively permeable membrane.
3. A cell is isotonic to a solution of 0.01% sugar.
a. What concentration would by hypertonic? >0.01%
b. What concentration would be hypotonic? <0.01%
4. a) What happens to an animal cell in a hypotonic solution? it swells and bursts
b) What happens to an animal cell in a hypertonic solution? It loses water to medium -- shrivels up.
5. Turgor pressure is best exemplified by placing a plant cell in a hypotonic solution.
6. Give an example:
a. of diffusion in the body the movement of O2 from the air sacs into the blood
b. of facilitated transport some sugars enter the cell more quickly than others
c. of active transport the concentration ([]) of Na is greater outside a cell, the [] of K is greater inside a cell
7. List 3 ways in which active transport differs from the process of diffusion across a cell membrane.
i. goes from area of less[] to area of greater
ii. requires carrier protein
iii. requires expenditure of energy
Raycroft 4.5 Worksheet - Cell Membrane - Review Worksheet Key - Page 1
