SINCLAIR COMMUNITY COLLEGE BIO 2206 EXAM 2 | COMPREHENSIVE STUDY GUIDE,
PRACTICE QUESTIONS AND ANSWERS 2026/2027
Positive Gram tests will be ____ and Negative Gram Test will be ___ - ANS ✔✔purple, pink/red
Compare and Contrast the difference between differential and selective media - ANS ✔✔・
differential is used to differentiate between bacterial cultures based on their biochemical
properties
・selective is used to encourage the growth of specific microorganisms while inhibiting the
growth of others.
what is the function of pH indicators - ANS ✔✔the pH of the solution can be determined
visually or spectroscopically by changes in absorption and/or emission properties.
what are the steps of a bacteria smear? - ANS ✔✔1. Initial your slide with a pencil so alcohol
will not remove it.
2. Draw a circle in the center (underside) of your slide with a wax pencil
3. Sterilize a loop using a flame
4. Transfer a loop of bacteria using an inoculation loop. Touch lightly into the center of the slide.
5. Sterilize the loop again using a flame
6. Allow the slide to dry completely, wait aproximately 10 minutes
7. Heat fix the bacteria to the slide. Pass the underside of the slide through the flame 3 times. 1
second each pass.
What are the steps of gram staining? - ANS ✔✔1. add a few drops of crystal violet (primary
stain) to cover the bacteria, let stand for 1 minutes
2. rinse the slide by holding it at a 45 ° angle and applying several drops of Gram's Iodine
3. Add a few more drops of Gram's Iodin to cover the bacteria, let stand for 2 minutes
PRACTICE QUESTIONS AND ANSWERS 2026/2027
Positive Gram tests will be ____ and Negative Gram Test will be ___ - ANS ✔✔purple, pink/red
Compare and Contrast the difference between differential and selective media - ANS ✔✔・
differential is used to differentiate between bacterial cultures based on their biochemical
properties
・selective is used to encourage the growth of specific microorganisms while inhibiting the
growth of others.
what is the function of pH indicators - ANS ✔✔the pH of the solution can be determined
visually or spectroscopically by changes in absorption and/or emission properties.
what are the steps of a bacteria smear? - ANS ✔✔1. Initial your slide with a pencil so alcohol
will not remove it.
2. Draw a circle in the center (underside) of your slide with a wax pencil
3. Sterilize a loop using a flame
4. Transfer a loop of bacteria using an inoculation loop. Touch lightly into the center of the slide.
5. Sterilize the loop again using a flame
6. Allow the slide to dry completely, wait aproximately 10 minutes
7. Heat fix the bacteria to the slide. Pass the underside of the slide through the flame 3 times. 1
second each pass.
What are the steps of gram staining? - ANS ✔✔1. add a few drops of crystal violet (primary
stain) to cover the bacteria, let stand for 1 minutes
2. rinse the slide by holding it at a 45 ° angle and applying several drops of Gram's Iodine
3. Add a few more drops of Gram's Iodin to cover the bacteria, let stand for 2 minutes
