Yeast is different from Penicillium and Rhizopus in being

Options

A. Having ascospores as the spores of sexual reproduction
B. They are unicellular without mycelium
C. Having unseptate hyphae
D. They are multicellular with septate hyphae

Answer

To solve the question of how yeast is different from Penicillium and Rhizopus, we will follow these steps:

### Step 1: Identify the Organisms
- **Yeast**: A unicellular fungus primarily belonging to the genus Saccharomyces.
- **Penicillium**: A genus of fungi that is multicellular and belongs to the group called Ascomycetes.
- **Rhizopus**: A genus of fungi commonly known as bread mold, which is also multicellular and belongs to the group called Phycomycetes.

### Step 2: Classify the Organisms
- **Yeast** is classified as a unicellular organism.
- **Penicillium** and **Rhizopus** are classified as multicellular organisms that form a network of hyphae.

### Step 3: Understand the Structure
- **Yeast**: Does not form a mycelium; it exists as individual cells.
- **Penicillium and Rhizopus**: Form a mycelium, which is a network of hyphae that constitutes the thallus of the fungus.

### Step 4: Compare the Groups
- **Yeast** is classified under Ascomycetes (Sac fungi).
- **Penicillium** is also classified under Ascomycetes.
- **Rhizopus** is classified under Phycomycetes.

### Step 5: Conclusion
The primary difference is that yeast is unicellular, while both Penicillium and Rhizopus are multicellular and form a mycelium. Therefore, the correct answer to the question is that yeast is different from Penicillium and Rhizopus in being unicellular.

### Final Answer
Yeast is different from Penicillium and Rhizopus in being unicellular.

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