Cell Transport Notes
Biology 5.0
Name: ________________________
Date: ______________ Period: ___
Activating Prior knowledge:
1. Define the term homeostasis.
2. Give the function of each of the following organelles:

Cell membrane –

Lysosome –

Golgi Apparatus –
3. How does the cell membrane maintain homeostasis?
4. Label and describe as many parts/features of the cell membrane as you can.
5. Distinguish between peripheral and integral proteins. Put in diagram above.
Key Terms Associated with Transport:
Describe what happens in this picture
Difference in
Concentration
Down the concentration gradient:
Gradient
Up the concentration gradient:
When the concentration is the
Equilibrium
____________________ throughout
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Types of Transport:
movement of molecules ____________ their
Passive
concentration gradient _______________ the
Transport
_____________________________________
movement of molecules _______ their
Active
concentration gradient ______________ the
Transport
_____________________________________
Passive Transport:
Determining Factors
Types of Passive Transport

1)

2)

3)
4)

Process by which
Diffusion
tend to move from an area where they are
______________ concentrated to an area where they are _______________ concentrated

____________________ transport
______________________ of __________________ through a _________________
________________________________________________
Osmosis

____________________ transport

from an area of ________________ water concentration to an area of
________________ water concentration
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Direction of Osmosis:
Type of
Solution
Description of Solution
Illustration
Effect on Cell
Isotonic
Hypotonic
Hypertonic
Water diffuses from a _____________________ solution to a ____________________ solution.
Dealing with Osmosis
 Plants (root cells)
in a
environment
 The swelling
when the cell
is pressed against the cell
 The cell wall is strong enough to resist the pressure, called
Turgor Pressure
Definition:
Cytolysis
Definition:
Plasmolysis
Definition:
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Unicellular freshwater organisms (Paramecium) live in a
Contractile _______________________ environment
Vacuole
Collects excess ___________ and pumps it ________ of cell
Review Questions:
1. Toward what condition does diffusion eventually lead, in the absence of other influences?
2. How is osmosis related to diffusion?
3. If the concentration of solute molecules outside a cell is lower than the concentration in the cytoplasm, is the
external solution hypotonic, hypertonic, or isotonic to the cytosol?
4. Sea water has a higher concentration of solutes than do human body cells. Why might drinking large
amounts of sea water be dangerous to humans?
Facilitated Diffusion
 Movement of specific molecules across cell membranes through ___________________________________
 ____________________ transport
 _______________________ of materials across a cell membrane assisted by _________________________
 Move molecules, (that cannot diffuse easily), ___________________ their concentration gradient
 Move __________ or __________ of cell
 Examples:
 Assisted by
on the membrane
 ______________________ to one type molecule
 More protein =
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Diffusion Through Ion Channels
 Provide
for
to
diffuse
 __________________________ to ____________________
 Two types
1. ___________________________
2. ___________________________ - open and close in
_____________________________________
Active Transport:
 Cells use
to move
concentration gradient
 __________________ supplies
 ____________________________ act as _________________
 Sodium – Potassium Pump: In animals, cells transport Na+ and K+
_____ the concentration gradient
 ____ Na+ moved outside of cell and ____ K+ moved inside cell
Steps for Transport:
1. 3 Na+ bind to carrier protein in cytoplasm -Carrier protein splits phosphate group from ATP
2. P group binds with carrier protein—shape changes—releases Na+
3. Now can pick up 2 K+ on outside
4. Carrier protein changes shape releases K+
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Exocytosis and Endocytosis
 Transport
across membrane
 Transport a
of
molecules
 ____________________ used
 Exporting ______________ molecules outside of cell
 Process:
Exocytosis

Packaged in _____________________

_____________________ transports to cell membrane

Vesicle __________________ to __________________

Contents __________________

Vesicle becomes part of __________________
 Cells __________________ (ingest) substances
 Process:

Endocytosis
Depression in cell membrane folds in __________________ material from
__________________ of the cell

__________________ off forming a membrane-bound ________________

Vesicle fuses with __________________

Fuse with other __________________
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Type of
Endocytosis
Description of Process
Pinocytosis
Phagocytosis
ReceptorMediated
Review Questions:
1. Explain the difference between passive and active transport.
2. What provides the energy that drives the sodium-potassium pump?
3. Explain the difference between phagocytosis and pinocytosis.
4. During intense exercise, potassium tends to accumulate in the fluid surrounding muscle cells. What
membrane protein helps muscle cells counteract this tendency? Explain your answer.
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