Step 1: Understanding Baker’s yeast.
Baker’s yeast is a microorganism used in baking industries for fermentation of sugars to produce carbon dioxide.
Step 2: Role in fermentation.
It converts glucose into ethanol and CO$_2$, which helps dough rise in bread making.
Step 3: Identification of organism.
The species used as baker’s yeast is Saccharomyces cerevisiae, a unicellular fungus.
Step 4: Evaluating other options.
- Chaetomium: soil fungus, not used in baking.
- Candida: opportunistic yeast, not baker’s yeast.
- Rhizopus: bread mold, not yeast.
Step 5: Biological reasoning.
Saccharomyces cerevisiae is industrially important due to its strong fermentative ability.
Step 6: Final conclusion.
Therefore, Baker’s yeast is Saccharomyces cerevisiae.