Mollie Deuel's Teaching Portfolio

Cell Membrane and Cellular Transport Engineering Design Unit CLICK HERE

• Teacher's Manual

• Pre & Post Assessments

• Student Worksheet and Analysis Questions

• Materials Cost Slips

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Cell Membrane, Cellular Transport & Engineering Design PowerPoint CLICK HERE

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Essential Questions:

 

How does the cell membrane help maintain homeostasis inside of the cell?

What are the steps of the Engineering Design Process?

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Virginia Standards of Learning (SOLs):

Primary SOL’s

BIO.3 The student will investigate and understand relationships between cell structure and function. Key concepts include
       d) the cell membrane model
       e) the impact of surface area to volume ratio on cell division, material transport, and other life processes

BIO.4 The student will investigate and understand life functions of Archaea, Bacteria and Eukarya. Key concepts include

       a) comparison of their metabolic activities

       b) maintenance of homeostasis

       d) human health issues

 

Secondary SOL’s

BIO.1 The student will demonstrate an understanding of scientific reasoning, logic, and the nature of science by planning and conducting investigations in which
       f) sources of error inherent in experimental design are identified and discussed.

 

Next Generation Science Standards:

• HS-LS1-2. Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms.

• HS - ETS1-1. Analyze a major global challenge to specify qualitative and quantitative criteria and constraints for solutions that account for societal needs and wants.

• HS - ETS1-2. Design a solution to a complex real-world problem by breaking it down into smaller, more manageable problems that can be solved through engineering.

• HS - ETS1-3. Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics as well as possible social, cultural, and environmental impacts. 

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Scenario:

German physiologist Rudolph Virchow first theorized cellular pathology--disease at the cellular level--in the 1850s. Today, new treatments for many disorders are a direct result of understanding a disease process at the cellular level. Abnormalities in organelles such as the cell membrane, can cause whole-body symptoms.

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Cystic fibrosis was first described in medical journals in the late 1930’s as a defect in the pathways leading from certain glands. This caused an array of problems including thick mucus in the lungs and frequent infection; a clogged pancreas, preventing digestive juices from reaching the intestines; and salty sweat. Cystic fibrosis is just one example of how genetic abnormality causes symptoms felt at a whole-body level.

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The plasma membrane plays an integral role in maintaining homeostasis by controlling what comes into and out of the cell. We have discussed how small defects that result in some loss of function of the plasma membrane can result in major disorders, such as Duchenne Muscular Dystrophy and Cystic Fibrosis.

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Some small, non-polar molecules are able to cross the plasma membrane along the concentration gradient directly through the phospholipid bilayer. Other smaller charged molecules, like water and charged ions, are able to cross the membrane via channel proteins through the process of facilitated diffusion. Some substrates need to be pumped across the membrane against the concentration gradient (or may be too large to cross the membrane) and require an energy input and/or the help of carrier proteins to cross the membrane via active transport.

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In this design challenge, you will be acting as biomedical engineers who are responsible for designing a cell membrane that allows different substrates to cross it via a variety of “transport and channel proteins” to replace the faulty membranes in cystic fibrosis patients.

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Your model should demonstrate the phospholipid bilayer and include representations of: Hydrophobic tails, Hydrophilic heads, Transport proteins, Channel proteins and Cholesterol that will be able to transmit four materials that represent different types of substrates that would need to enter/exit a cell.  These substances may enter via simple diffusion, facilitated diffusion or active transport.  Your prototype must represent each of these processes in the sense of whether or not extra energy (ATP) is needed.

 

Here are the materials that will need to cross your model membrane, the type of cell transport they would require, and what will be representing each:

 

    Substance:                                Type of Cell Transport:                         Represented by:

      O2/CO2                                                  Simple Diffusion                                             Sand

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    Water & Ions                           Facilitated Diffusion via channel proteins                      Water

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      Glucose                                      Active Transport via specialized                            Pom-Poms     

  (moving against                                     transmembrane proteins

     the gradient:

     ex. intestine)

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     Mineral ions                                Active Transport via specialized                              Marbles

  (moving against                                     transmembrane proteins

     the gradient:

     ex. in plant roots)

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Materials Available:

 

• Styrofoam ball - $5.00

• Tape (6”) - $ 3.00

• Cotton balls (x5) -$3.00

• Toothpicks (x10) - $ 2.00

• Drinking Straw - $1.00

• Coffee Stirrers (x5) – $2.00

• Rubber Band – $3.00

• Paper Clips (x 10) - $2.00

• Craft Foam (2”x2”) - $2.00

• String (6”) - $2.00

• Cheese cloth (2”x2”) - $1.00

• Pipe cleaner – $1.00

• Aluminum Foil (2”x2”) - $1.00

• Play-doh (1” ball) – $3.00

• Q-tips (x25)-$3.00

 

 

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