Which of the statements given below is not true about formation of Annual Rings in trees?

Options

A. Annual ring is a combination of spring wood and autumn wood produced in a year .
B. Differential activity of cambium causes light and dark bands of tissue - early and late wood respectively
C. Activity of cambium depends upon variation in clmate
D. Annual rings are not prominent in trees of temperate region .

Answer

To determine which statement is not true about the formation of annual rings in trees, we can analyze each statement step by step:

1. **Understanding Annual Rings**: Annual rings, also known as growth rings, are formed as a result of the seasonal activity of the cambium, which is a layer of tissue responsible for secondary growth in plants.

2. **Analyzing the Statements**:
- **Statement 1**: "Annual ring is a combination of spring wood and autumn wood produced in a year."
- This statement is true. Annual rings consist of early wood (spring wood) and late wood (autumn wood) that are produced in one growing season.

- **Statement 2**: "Differential activity of cambium causes light and dark bands of tissue early and late wood respectively."
- This statement is also true. The cambium is more active in spring, producing lighter, wider cells (spring wood), and less active in autumn, producing darker, denser cells (late wood).

- **Statement 3**: "Activity of cambium depends upon the variation in climate."
- This statement is true as well. The cambium's activity is influenced by seasonal changes in climate, which affect growth rates.

- **Statement 4**: "Annual rings are not prominent in the trees of the temperate region."
- This statement is false. Annual rings are very prominent in trees of temperate regions due to distinct seasonal changes that affect cambial activity.

3. **Conclusion**: The statement that is not true about the formation of annual rings in trees is the fourth one: "Annual rings are not prominent in the trees of the temperate region."

### Final Answer:
The statement that is not true is: "Annual rings are not prominent in the trees of the temperate region."