Cellular Transport
SBI4U Biochemistry
Concept Presentation
By: Kasia Hirniak
Background Knowledge
http://www.youtube.com/watch?v=4c1r8ydVuds
Curriculum Expectations
Overall Expectation
 B2. investigate the chemical structures,
functions, and chemical properties of
biological molecules involved in some
common cellular processes and
biochemical reactions
Curriculum Expectations
Specific Expectations
 B2.2 plan and conduct an investigation to demonstrate
the movement of substances across a membrane (e.g.,
the effects of salt water and distilled water on a
potato).
 B3.6 describe the structure of cell membranes
according to the fluid mosaic model, and explain the
dynamics of passive transport, facilitated diffusion,
and the movement of large particles across the cell
membrane by the processes of endocytosis and
exocytosis.
Advance Preparation
Students should have a good understanding of the
following concepts:
 Cell structure and function
 Molecules are always in motion
 Cell permeability
 Cells store and use energy for building materials,
transport and controlling life processes
 Cells need chemical compounds to perform
functions and build structures
 The law of diffusion
Student Difficulties
Student Difficulty
•Students may have difficulty learning to
think about the processes at the
molecular level.
•Students may believe that in diffusion
when the molecules are evenly spread
out they stop moving.
•Students may confuse osmosis and
diffusion by thinking they are the same.
•Students may confuse diffusion with
dissolving.
•Students may find the concept of
tonicity (isotonic, hypotonic, hypertonic)
difficult to understand. They may have
hard time remembering which direction
water moves in each of the three types of
solutions.
Rectification
Showing students animations and videos
can help them visualize how the
processes work.
Engaging students in a lab or showing
them a demonstration can help them
differentiate between different processes.
Lesson Sequence
Lesson 1: The Structure and Composition
of the Cell Membrane
Lesson 2: Passive and Active Transport
Lesson 3: Cellular Transport Stations
Lesson 1: Cell Membrane
Introductory Group Activity:
Building a model of the cell membrane using
metal paper fasteners
Topics Covered:
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•
•
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Properties of lipids
Structure of the phospholipid
molecule
Structure of the cell membrane
Components of the cell membrane
Assessment:
Fluid Mosiac Model Video:
http://www.youtube.com/watch?v=ULR79TiUj80
Journal Entry
Lesson 2: Active and
Passive Transport
Topics Covered:
•
•
Passive Transport: Diffusion, Osmosis, Facilitated Diffusion
Active Transport: Endocytosis, Exocytosis
Teaching Tools:
• Introductory Salty Potato
Demonstration
• Osmosis Gizmo Activities
• Egg Osmosis Lab
• Active Transport Video
Assessment:
http://www.youtube.com/watch?v=0c8acUE9Itw
Gizmos Worksheets/
Lab Report
Lesson 3: Cellular Transport
Stations
Task:
Students will be divided into groups and will rotate
around the classroom visiting stations and
completing Cellular Transport activities
Assessment:
Teacher Checklist
Self/Peer
Evaluation
Quiz
Station 1: Building a Model of the
Cell Membrane
Materials:
 Cotton Swabs
 Pipe Cleaners
 Drinking Straw
Station 2: Labeling
Task:
Students label the
following
components of the
cell membrane
 Phospholipids
 Glycoproteins
 Cholesterol
 Hydrophobic fatty
acids
 Protein channels
Station 3: Cell Transport
Classification
Task:
Students indicate the type of
transport illustrated on pictures
provided.
Station 4: How do specific
substances cross the cell
membrane?
Task:
Students predict the mode of transport of the following
substances
 Oxygen
 Neutotransmitters
 Pepsin
 Glucose
 Virus
 Sodium Ions
Applications
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The effect of Marathon runners drinking
fluids that contain sugar and salt.
The reason for gardeners to soak fresh
vegetables from the garden in saltwater
before rinsing them and soaking them in
freshwater.
Grocery stores misting vegetables to
preserve their freshness.
Osmosis being vital to many body
processes, including: blood filtration by
the kidneys and the workings of the
nerves.
The importance of diffusion in cellular
respiration, wherein cells take in oxygen
and push out waste carbon dioxide.
Malfunction of the chlorine channel
causes cystic fibrosis.
The secretion of insulin from pancreatic
cells into the blood by exocytosis to
lower blood sugar level preventing
diabetes.
Build-up of cholesterol in cell
membranes leading to atherosclerosis.
Annotated Internet
Addresses/References
 http://science-class.net
 provides resources for elementary and middle school science teachers,
lessons/slideshows, labs, simulations/videos, student
worksheets/handouts, quizzes, study notes, review games etc
 http://home.earthlink.net/~shalpine/anim/Life/memb.htm
 an interactive demonstration of the structure and function of the cell
membrane.
 http://www.johnkyrk.com/diffusion.html
 a simple animation showing a high concentration of molecules in the
center of the page. As you watch, they will diffuse through random
molecular motion.
 http://www.wisc-online.com/objects/index_tj.asp?objid=AP11003
 a tutorial that will help understand the process of osmosis.
 http://www.wisc-online.com/objects/index_tj.asp?objid=AP11203
a learning activity showing endocytosis, exocytosis, and active transport.
 http://www.youtube.com/watch?NR=1&v=Kd3LorZcJew
 video showing the sodium/potassium pump as an example of active
transport