Q. The number of stomata and epidermal cells in $1\ {mm}^{2}$ leaf area of lower epidermis of the leaves of X, Y and Z plants are given below. Arrange the plants in decreasing order of their stomatal index. [table] Plant | Number of Stomata | Number of Epidermal Cell ; X | 30 | 150 ; Y | 60 | 240 ; Z | 90 | 400 [/table]
A) X, Y, Z
B) Y, Z, X
C) Z, Y, X
D) Y, X, Z
Explanation
Stomatal index $(SI) = \frac{S}{S\ + \ E} \times 100$ [table] Plant | Number of Stomata (S) | Number of Epidermal Cell (E) | SI ; X | 30 | 150 | 16.6 ; Y | 60 | 240 | 20.0 ; Z | 90 | 400 | 18.3 [/table] So, the arrangement of plants in decreasing order of their stomatal index in Y, Z, X.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.