You Are Working in a Laboratory, Making Media for Growing

question 55

Multiple Choice

You are working in a laboratory, making media for growing bacteria. The recipe you are following calls for the addition of TRIS buffer. You can't find any TRIS in the lab, so you decide to leave it out of the medium. Select the False statement regarding your decision.

• A) The medium will likely not be useable, because bacteria live within a narrow pH range, near pH 14.
• B) Maintaining the correct pH is essential for cells, because crucial molecules such as enzymes may lose function in the incorrect pH.
• C) Buffers are added to solutions to stabilize the hydrogen ion concentration of that solution.
• D) The acidity of the medium without buffer may change dramatically as the bacteria grow.
• E) The medium will likely not be useable, because bacteria live within a narrow pH range, near neutral.

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Definitions:

Larynx

The voice box located in the throat, responsible for producing sound, protecting the airway during swallowing, and regulating airflow during breathing.

Alveoli

Small air sacs in the lungs where the exchange of oxygen and carbon dioxide takes place.

Costal Angle

The angle formed by the meeting of the lower borders of the rib cage, usually becoming more acute when the ribs are drawn together during inspiration.

Kyphosis

An excessive outward curvature of the spine, leading to a hunched back appearance.