Question

Smallest leaf occurs in
A) Victoria
B) Wolffia
C) Cycas
D) Spiraea

Answer 1

Hint: Leaves come in different shapes and sizes. Sometimes tall trees may have very small leaves, while short monocotyledons have very large leaves. Size is affected by the available water and the temperature and sunlight of the habitat.

Complete answer:
Victoria plants belong to the water lily family. They float on the surface of water bodies, and are large, plate-like structures. The largest leaves are found in Victoria amazonica, which may have a diameter as much as three metres. Option A is incorrect.

Wolffia is also known as duckweed and includes the smallest flowering plant. This genus has 11 members. These plants are found floating on the surfaces of still water bodies like ponds, and small streams. These plants have reduced stems and leaves, and do not have true roots or a complete vascular system. The entire plant may be only about a millimetre in size. In fact, the leaves have been reduced to a thallus which is hard to distinguish. Option B is the correct answer.

Cycads plants are gymnosperms and their leaves are fronds similar to the coconut plants. Their leaves are of two types: scaly and foliage. Option C is incorrect.

Spiraea is a genus of flowering plants which are deciduous. They belong to the same family as the rose, and may range in height up to a few feet tall. The leaves are generally oval or lanceolate. Option D is incorrect.

Hence the correct answer is option ‘B’.

Note:Besides the obvious function of leaves being green and carrying out photosynthesis, they may also be modified for protective or gripping functions. For example, the thorns of the cactus are modified leaves, and leaf tendrils in some climbers are for holding on to support.