In some cyanobacteria, there are membranous extensions into the cytoplasm called ______which contain pigments.

Options

A. Chromatophores
B. mesosome
C. phycobilisomes
D. all of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of membranous extensions found in some cyanobacteria that contain pigments.

2. **Analyzing the Options**:
- **Option 1: Chromatophores**: These are known to be pigment-containing structures found in cyanobacteria. They play a role in photosynthesis by reflecting light.
- **Option 2: Mesosomes**: These are invaginations of the plasma membrane in bacteria, not specifically related to pigments.
- **Option 3: Phycobilisomes**: These are protein complexes associated with the thylakoid membranes in cyanobacteria but are not membranous extensions into the cytoplasm.
- **Option 4: All of the above**: This option cannot be correct since not all the previous options are correct.

3. **Identifying the Correct Answer**: Based on the analysis, the correct answer is **Chromatophores**.

4. **Final Answer**: In some cyanobacteria, there are membranous extensions into the cytoplasm called **Chromatophores**, which contain pigments.

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