Question

Bipinnate leaves are characteristic of
A. Cruciferae
B. Solanaceae
C. Papilionoideae
D. Mimosoideae

Answer 1

Hint: The leaf is a green, flat, thin, expanded lateral structure of the plant stem. This part is produced at a node and holds a bud in its axil. It is exogenous in origin which is produced from the leaf primordium of the shoot apex. A leaf appears green due to the presence of the photosynthetic pigment chlorophyll.

Complete answer:
Leaves can be defined as thin, flat, green expanded parts of a plant that are responsible for photosynthesis and respiration in the plants. It forms at the node laterally. A leaf originates from shoot apical meristems.
Generally, in a leaf, there are three parts which are the leaf base, petiole, and lamina. The leaf base is the part where a leaf attaches to the stem. The petiole is the long, thin, stalk-like structure that connects the leaf blade to the stem. The lamina is the green, flat surface of the leaves which is also known as the leaf blade.
Leaves can be classified into two categories which are simple leaf and compound leaf. When a single lamina is linked to the main stem by a petiole, then it will be called a simple leaf such as guava leaves. In the case of a compound leaf, the leaf consists of two or more leaflets. The midrib of a compound leaf is branched into different leaflets. It is linked by a single petiole and seen in plants such as pea, palm leaves. The compound leaves are further classified into different types of leaves; Palmately Compound Leaf and Pinnately Compound Leaf.
The leaflets are attached at the tip of the petiole in a palmately compound leaf such as silk cotton while in a pinnately compound leaf, the midrib of the leaf is divided into several leaflets. The leaflets are attached by a common axis such as neem. Bipinnate leaf is a category of a pinnately compound leaf. In this case, a secondary axis holds the leaflet which is formed by the central axis. Each leaflet is known as a pinnule. This type of leaves can be found in Mimosa pudica which belongs to the family of Mimosoideae.
Thus, the right option is D.

Note: The leaf plays a vital role in the growth and development of the plant. Two major processes; photosynthesis and respiration take place in the leaves. The structure of the leaves may vary in the different species of plants. There are two types of leaves found; simple and compound leaves. The bipinnate leaf is a type of compound leaves in which a secondary axis holds the leaflet which is formed by the central axis. This type of leaves can be seen in the plant belonging to the family of Mimosoideae.