Explain how the phosphate buffer in the media works to maintain a constant pH of 7 throughout the incubation even though S. pyogenes produces acid.
The ingredients in the MR/VP Broth are:
Peptone (protein) 7g
Glucose 5g
Phosphate buffer 5g
Distilled water 1L
Examine the above figure. This figure shows how the pH in the Methyl Red and Voges-Proskauer (MR-VP) broth changes during incubation from time zero to 48 hours with 1) an MR-positive bacteria and 2) a MR-negative bacteria.
We know from the Exercise 5-2 Phenol Red Broth that all of the Unknown Bacteria Species ferment glucose with acid end products. Streptococcus pyogenes is MR negative and VP negative. S. pyogenes does not perform a mixed acid fermentation (purple dashed line). However, S. pyogenes does produce acid from glucose fermentation. Explain how the phosphate buffer in the media works to maintain a constant pH of 7 throughout the incubation even though S. pyogenes produces acid.
![](/static/compass_v2/shared-icons/check-mark.png)
Trending now
This is a popular solution!
Step by step
Solved in 2 steps
![Blurred answer](/static/compass_v2/solution-images/blurred-answer.jpg)
![Human Anatomy & Physiology (11th Edition)](https://www.bartleby.com/isbn_cover_images/9780134580999/9780134580999_smallCoverImage.gif)
![Biology 2e](https://www.bartleby.com/isbn_cover_images/9781947172517/9781947172517_coverImage_Textbooks.gif)
![Anatomy & Physiology](https://www.bartleby.com/isbn_cover_images/9781259398629/9781259398629_smallCoverImage.gif)
![Human Anatomy & Physiology (11th Edition)](https://www.bartleby.com/isbn_cover_images/9780134580999/9780134580999_smallCoverImage.gif)
![Biology 2e](https://www.bartleby.com/isbn_cover_images/9781947172517/9781947172517_coverImage_Textbooks.gif)
![Anatomy & Physiology](https://www.bartleby.com/isbn_cover_images/9781259398629/9781259398629_smallCoverImage.gif)
![Molecular Biology of the Cell (Sixth Edition)](https://www.bartleby.com/isbn_cover_images/9780815344322/9780815344322_smallCoverImage.gif)
![Laboratory Manual For Human Anatomy & Physiology](https://www.bartleby.com/isbn_cover_images/9781260159363/9781260159363_smallCoverImage.gif)
![Inquiry Into Life (16th Edition)](https://www.bartleby.com/isbn_cover_images/9781260231700/9781260231700_smallCoverImage.gif)