A stem with jointed stem is called culm. It has distinct nodes and internodes. It is a characteristic of

Options

A. palms
B. bamboo
C. Pinus
D. All correct.

Answer

To solve the question regarding the stem with jointed structure known as "culm," we need to identify which plant characteristic it describes. Here’s the step-by-step solution:

### Step 1: Understand the term "culm"
A culm refers to a type of stem that is jointed and has distinct nodes and internodes. This structure is commonly associated with certain types of plants.

**Hint:** Think about plants that have a segmented or jointed appearance in their stems.

### Step 2: Identify the characteristics of culm
The culm is characterized by:
- Erect and unbranched stems
- Distinct nodes (the points where leaves or branches attach)
- Distinct internodes (the sections of the stem between the nodes)

**Hint:** Recall the structural features of plants that might fit this description.

### Step 3: Analyze the options provided
The options given are:
1. Palms
2. Bamboo
3. Pinus
4. All correct

**Hint:** Consider which of these plants typically have stems that are jointed.

### Step 4: Evaluate each option
- **Palms**: They have a stout, unbranched stem known as a "coconut" or "trunk," but it does not have distinct nodes and internodes like a culm.
- **Bamboo**: This plant has a culm structure, with distinct nodes and internodes, making it a strong candidate.
- **Pinus**: This refers to coniferous trees that have an excurrent type of stem, which does not match the description of a culm.
- **All correct**: This option would only be valid if all the previous options fit the description, which they do not.

**Hint:** Focus on the specific characteristics of bamboo and how they relate to the definition of culm.

### Step 5: Conclusion
Based on the analysis, the correct answer is **bamboo**. Bamboo stems are indeed characterized by the culm structure, which includes distinct nodes and internodes.

**Final Answer:** Bamboo