Question

When you add yeast to dough, it rises because

• A. Yeast cells reproduce by budding.
• B. Budding yeast cells form colonies.
• C. The rapidly reproducing yeast cells release carbon dioxide due to anaerobic respiration.
  
• D. None of the above

Answer 1

Answer: (C)

The rapidly reproducing yeast cells release carbon dioxide due to anaerobic respiration.

Yeast are the organism that executes the process of fermentation in which they break down the sugar into its simpler forms for obtaining energy. In this process carbon dioxide and alcohol are also forms and CO${}_2$ helps the dough to rise. The process is favorable in humid and warm conditions in colder environment it slows down.

So, the correct answer is 'The rapidly reproducing yeast cells release carbon dioxide due to anaerobic respiration'.