Question

Bipinnate leaves and spiny stipulates are the characteristics of family
A. Papilionaceae
B. Caesalpinioideae
C. Mimosoideae
D. Malvaceae

Answer 1

Hint: This family of trees is mostly found in subtropical and tropical climate. Mimosa, entada, acacia, etc are some examples of this family.

Complete Answer:
- Pinnation is a formulation of feather-like or multi-divided features on both sides of a common axis. Biological morphology, crystals such as ice or metallic crystals, erosion patterns and stream beds, contributes to pinnation.
- Botanically, pinnation is a mixture of distinct structures that occurs on a common axis at many points, including the leaflets, veins, lobes, branches, or appendices. For instance, pinnate, compound blades with leaflets arranged on both sides of a rachis.
- Bipinnate leaves are distinguished in the length of main rachis (primary rachis) by the presence of secondary rachis. The secondary rachii has pinnately arranged leaflets and hence is doubling pinnate, therefore the name is bipinnate.
- A stipule is a leafstalk base (petiole) that is borne from one side or the other (sometimes just one side). A pair of stipules is known to be part of a leaf anatomy, although the stipules are not evident, or totally lack, in many species. If they are long and pointy, a stipule is called spiny. They are commonly used for animal deterrence.
- Papilionaceae is simple, pinnate or palmate, with leaves that are non-spiny.
- Cesalpinoideae have single or pinnate compounds, non-spiny leaves are listed.
- Mimosoideae have simple or bipinnate or palmately compound, spiny stipulated leaves.
- Malvaceae is compounded with simple or palmate, with non-spiny leaves.

Thus, the correct answer is option C. i.e., Mimosoideae.

Note: The mimosoideae are trees, herbs, lianas and shrubs, which grow mainly in a tropical and subtropical environment. They include a clad, previously placed in the Fabaceae (Leguminosae) flora family at the level of the subfamily or the family. Mimosoideae refer to what was formerly called the Mimosaceae tribe in previous classifications.