Membrane bound organelles are absent in

Options

A. Streptococcus
B. Chlamydomonas
C. Plasmodium
D. Saccharomyces.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which organisms lack membrane-bound organelles. To answer this, we need to differentiate between prokaryotic and eukaryotic organisms.

2. **Defining Prokaryotic and Eukaryotic Organisms**:
- Prokaryotic organisms (like bacteria) do not have membrane-bound organelles and their genetic material is not enclosed in a nucleus but is instead found in a region called the nucleoid.
- Eukaryotic organisms (like fungi, plants, and animals) have a well-defined nucleus and membrane-bound organelles.

3. **Analyzing the Options**:
- **Option 1: Streptococcus** - This is a type of bacteria, which are prokaryotic. Therefore, they lack membrane-bound organelles.
- **Option 2: Chlamydomonas** - This is a type of green algae and is eukaryotic, thus it has membrane-bound organelles.
- **Option 3: Plasmodium** - This is a protozoan parasite and is also eukaryotic, meaning it has membrane-bound organelles.
- **Option 4: Saccharomyces** - This is a type of yeast (fungi) and is eukaryotic, so it also has membrane-bound organelles.

4. **Conclusion**: The only organism from the options provided that lacks membrane-bound organelles is **Streptococcus** (Option 1), which is a prokaryotic organism.

**Final Answer**: Membrane-bound organelles are absent in **Streptococcus**.

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