Conjoint collateral and open vascular bundles with xylem endarch occur in stem of

Options

A. Dracaena
B. Maize
C. Wheat
D. Helianthus

Answer

To solve the question "Conjoint collateral and open vascular bundles with xylem endarch occur in the stem of," we will follow these steps:

### Step 1: Understand Vascular Bundles
Vascular bundles are the part of the plant that contains xylem and phloem, which are responsible for the transport of water, nutrients, and food. There are two main types of vascular bundles: open and closed.

**Hint:** Remember that "open" vascular bundles contain cambium, while "closed" ones do not.

### Step 2: Identify Open vs. Closed Vascular Bundles
- **Open Vascular Bundles:** These contain cambium and are typically found in dicotyledonous plants (dicots).
- **Closed Vascular Bundles:** These lack cambium and are generally found in monocotyledonous plants (monocots).

**Hint:** Dicot plants usually have open vascular bundles, while monocot plants have closed vascular bundles.

### Step 3: Recognize the Structure of Vascular Bundles
- **Conjoint Collateral Vascular Bundles:** This means that the xylem and phloem are located next to each other within the same bundle.
- **Endarch Xylem:** This refers to the arrangement where the xylem develops towards the center of the stem, which is typical in many dicots.

**Hint:** Focus on the terms "conjoint" and "endarch" as they indicate specific structural arrangements in the vascular bundles.

### Step 4: Analyze the Options
Given the options, we need to identify which plant has the characteristics of having open vascular bundles with xylem that is endarch.

- **Dicot Examples:** Sunflower (Helianthus) is a well-known dicot that fits this description.
- **Monocot Examples:** Plants like maize, wheat, and Dracaena have closed vascular bundles.

**Hint:** Look for the plant that is classified as a dicot and has the correct vascular bundle structure.

### Step 5: Conclusion
After analyzing the options and understanding the characteristics of vascular bundles, we find that the correct answer is **Helianthus (Sunflower)**, which has conjoint collateral and open vascular bundles with endarch xylem.

**Final Answer:** The correct answer is **Helianthus**.