Articulated laticifers are

Options

A. (a) Formed by the fusion of cells
B. (b) A network like structure
C. (c) Found in the plants which are the source of commercial rubber
D. (d) All of these

Answer

**Step-by-Step Solution:**

1. **Definition of Articulated Laticifers**: Articulated laticifers are specialized elongated cells found in certain plants. They are responsible for the production of latex, a substance that serves various functions in plants.

2. **Location**: These laticifers are primarily located in the leaves and stems of some plants. Examples of such plants include rubber, papaya, and poppy.

3. **Composition of Latex**: The latex produced by articulated laticifers is a complex mixture that includes proteins, alkaloids, resin, starch, tannin, gum, and oil.

4. **Function of Latex**: The latex serves as a protective mechanism for the plant. When exposed to air, it coagulates and forms a gel-like substance that helps protect the plant from insects and other pests.

5. **Types of Laticifers**: There are two types of laticifers: articulated and non-articulated. The key difference is that articulated laticifers are arranged in a specialized network, while non-articulated laticifers consist of cells that are independent of each other.

6. **Characteristics of Articulated Laticifers**:
- They are formed by the fusion of cells.
- They create a network-like structure.
- They are found in plants that are sources of commercial rubber.

7. **Conclusion**: Based on the characteristics and functions of articulated laticifers, we can conclude that all the provided options (A, B, and C) are correct. Therefore, the correct answer is option D, which states that all of these characteristics apply to articulated laticifers.

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