Concept explainers
The unicellular alga Chlamydomonas reinhardtii has two flagella assembled from tubulin proteins. If a researcher changes the pH from approximately neutral (their normal growing condition) to pH 4.5, Chlamydomonas cells spontaneously lose their flagella. After the cells are returned to neutral pH, they regrow the flagella—a process called reflagellation. Assuming that you have deflagellated Chlamydomonas cells, devise experiments to answer the following questions:
Do new tubulin proteins need to be made for reflagellation to occur, or is there a reservoir of proteins in the cell?
Is the production of new mRNA for the tubulin proteins necessary for reflagellation?
What is the optimal pH for reflagellation?
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Biology: The Dynamic Science (MindTap Course List)
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