Question

Whorled, simple leaves with reticulate venation are present in
A. China Rose
B. Alstonia
C. Calotropis
D. Neem

Answer 1

Hint: As an expectorant the dried leaves of this herb is used. In order to cure skin infections, the leaves of this plant can be used.

Complete Answer:
A green, flat, thin, enlarged lateral appendage of the stem is the leaf. At a node, this section is born and bears a bud in its axil. It is exogenous in nature and grows from the shoot apex’s leaf primordium. The leaf's green colour is due to the presence of chlorophyll, a photosynthetic pigment. This pigment makes it possible for different plants to produce their organic food. The arrangement of veins and even the different veinlets in the leaves is venation. Different plants exhibit various venation styles.

Now, let us find the solution from the options-
- The leaves of China rose have reticulate venation but the other characteristics are not present in it. A single leaf emerging from the node is an alternative phyllotaxis. The China rose demonstrates this sort of phyllotaxis. Therefore, the option A is incorrect.
- The Alstonia leaves are simple, elliptical or ovate, linear to lanceolate and at the base are wedge-shaped. These are sessile and leathery ones. The blade of the leaf is dorsiventral, arranged with the whole margin in a whorl. The venation of the leaf is reticulated and ends in a marginal vein that has several veins. More than two leaves emerge from the node in whorled phyllotaxy. In Alstonia, it is visible.
- Sessile and sub-sessile, ovate, opposite, cordate at the base, are the leaves of Calotropis. Two leaves emerge in opposite directions from the node in opposite phyllotaxy. It's seen in the Calotropis. Therefore, the option C is incorrect.
- Leaves of neem are also reticulate and simple but not whorl. Therefore, the option D is incorrect.

Thus, the correct answer is option (B) Alstonia.

Note: Reticulate and parallel are the two forms of venation. The veinlets are distributed in a random order to establish a complex network of veinlets in a reticulate venation. The veinlets are arranged parallel to each other in parallel venation.