Anatomy Of Flowering Plants Question 85
Question: In trees, the growth rings represent:
Options:
A) Primary xylem
B) Secondary xylem
C) Secondary phloem
D) Cambium
Show Answer
Answer:
Correct Answer: B
Solution:
The inside of the tree gets a new vascular cambium every year and the outside of the cambium is responsible for the formation of xylem whose function is to transport water and minerals from the roots to the entire parts of the tree like shoots and roots.
The inside part of the cambium is developed into phloem having larger cells with thin cell walls and their function is to transport water and nutrients from the roots to the leaves of the trees.
When the trees grow in cooler temperatures the phloem is of lighter color due to the thin cell walls and in the summer season the growth of trees slows down and the walls of phloem thicken in order to prevent water loss.
This is responsible for the color variations within the tree. The xylem as it ages, it forms from the bark of the tree.
Thus, we can conclude that the formation of annual rings is due to the variations in the xylem of the tree, which is formed from the cambium.
BETA
