An elaborate network of filamentous proteinaceus structures present in the cytoplasm which helps in the maintenance of cell shape is called:

Options

A. Endoplasmic reticulum
B. Plasmalemma
C. Thylakoid
D. Cytoskeleton

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks for a network of proteinaceous structures in the cytoplasm that helps maintain cell shape.

2. **Identifying Possible Options:**
- **Endoplasmic Reticulum (ER):** This is a network of membranes involved in protein and lipid synthesis. It does not primarily maintain cell shape.
- **Plasma Lemma (Cell Membrane):** This defines the boundary of the cell but does not provide structural support for maintaining cell shape.
- **Thylakoid:** This is a structure found in chloroplasts involved in photosynthesis and is not related to cell shape maintenance.
- **Cytoskeleton:** This is a network of filamentous protein structures in the cytoplasm that provides structural support and maintains cell shape.

3. **Analyzing the Cytoskeleton:**
- The cytoskeleton is composed of three main types of protein filaments:
- **Actin Filaments:** These are involved in various cellular functions, including maintaining cell shape and enabling movement.
- **Microtubules:** These provide rigidity and shape to the cell and are involved in intracellular transport.
- **Intermediate Filaments:** These provide mechanical strength to the cell.

4. **Conclusion:** The elaborate network of filamentous proteinaceous structures that helps in the maintenance of cell shape is called the **Cytoskeleton**.

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