Question

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R:
Assertion A: Late wood has fewer xylary elements with narrow vessels.
Reason R: Cambium is less active in winters.
In the light of the above statements, choose the correct answer from the options given below:

• A. Both A and R are true but R is NOT the correct explanation of A
• B. A is true but R is false
• C. A is false but R is true
• D. Both A and R are true and R is the correct explanation of A

Answer 1

The Correct Option is D

Assertion A is true: Late wood, also known as "summer wood," is the portion of a tree ring that is formed during the later part of the growing season. It typically has fewer xylary (wood-forming) elements and narrower vessels compared to early wood.

Reason R is true and provides the correct explanation for Assertion A: The cambium, a layer of actively dividing cells between the xylem and phloem, is responsible for the formation of new xylem cells. During winters, the cambium becomes less active due to the colder temperatures and reduced metabolic activity. This reduced cambial activity leads to the formation of narrower vessels and fewer xylary elements in the late wood.

So, the correct option is (D): Both A and R are true and R is the correct explanation of A