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Lab 3: Worksheet

  • Page ID
    23984
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    Name: ______________________________

    Section: _____________________________

    Student ID#:__________________________

    Work in groups on these problems. You should try to answer the questions without referring to your textbook. If you get stuck, try asking another group for help.

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    1. Why are S. epidermidis and P. aeruginosa the same color with the simple stain? (1)

    2. What is being stained in a negative stain? (1)

    3. How does the charge of bacterial cells impact the staining procedures used? (1)

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    4. Which plate had gram-negative bacteria? What color were these bacteria and why? (2)

    5. Which plate had gram-positive bacteria? What color were they and why? (2)

    6. Draw the membrane layers of a gram-positive and gram-negative bacteria making sure to label the plasma membrane, peptidoglycan layers, periplasmic space, and LPS (3)


    Lab 3: Worksheet is shared under a CC BY-SA license and was authored, remixed, and/or curated by Nazzy Pakpour & Sharon Horgan.

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