Site of synthesis of cytokinin is

Options

A. Region of maturation of root
B. Region of active cell division
C. Region of active photosynthesis
D. Region of fully differentiated cells

Answer

To determine the site of synthesis of cytokinins, we can analyze the options provided in the question step by step:

### Step 1: Understand Cytokinins
Cytokinins are a class of plant hormones that promote cell division (cytokinesis) and are involved in various plant growth and developmental processes.

**Hint:** Cytokinins are primarily associated with promoting cell division in plants.

### Step 2: Evaluate the Options
1. **Region of maturation of root**: This region is primarily associated with gibberellins, which are another type of plant hormone that promotes growth but not specifically cell division.

**Hint:** Consider which hormones are associated with different regions of the plant.

2. **Region of active cell division**: This is the area where cytokinins are synthesized because their primary function is to stimulate cell division.

**Hint:** Think about where cell division occurs in plants and which hormones are involved.

3. **Region of active photosynthesis**: This area is primarily associated with auxins, which are involved in the growth and elongation of cells, not specifically in cell division.

**Hint:** Remember that different hormones have specific roles in plant processes.

4. **Region of fully differentiated cells**: In this region, abscisic acid (ABA) is more prevalent, which is involved in processes like stress response and does not promote cell division.

**Hint:** Fully differentiated cells are not actively dividing, so consider what hormones are active here.

### Step 3: Conclusion
Based on the analysis, the correct answer is the **region of active cell division**, as this is where cytokinins are synthesized to promote the process of cell division.

**Final Answer:** The site of synthesis of cytokinins is the **region of active cell division**.