The growth of roots and stems in length with the help of apical meristem is called

Options

A. primary growth
B. lateral growth
C. secondary growth
D. intercalary growth.

Answer

To answer the question regarding the growth of roots and stems in length with the help of apical meristem, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Apical Meristem**:
- Apical meristem is a region located at the tips of roots and shoots. It consists of actively dividing cells that contribute to the growth of the plant.

2. **Identify the Type of Growth**:
- The growth that occurs at the tips of roots and shoots is responsible for increasing the length of the plant. This type of growth is specifically associated with the apical meristem.

3. **Define Primary Growth**:
- The increase in length of the plant due to the activity of the apical meristem is referred to as primary growth. This growth is characterized by the elongation of the plant body.

4. **Differentiate from Other Growth Types**:
- It is important to distinguish primary growth from other types of growth:
- **Lateral Growth**: Refers to growth in thickness, which is not the focus here.
- **Secondary Growth**: Involves the increase in girth and is associated with vascular cambium, not apical meristem.
- **Intercalary Growth**: Occurs in certain plants at specific regions, but does not pertain to the general growth of roots and shoots.

5. **Conclude the Correct Answer**:
- Based on the understanding that apical meristem is responsible for the lengthening of roots and stems, we conclude that the correct term for this type of growth is **primary growth**.

### Final Answer:
The growth of roots and stems in length with the help of apical meristem is called **primary growth**.

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