The standard petal of a papilionaceous corolla is also called
- Pappus
- Vexillum
- Corona
- Carina
The Correct Option is B
Solution and Explanation
The correct answer is:
Option 2: Vexillum
Explanation:
In a papilionaceous corolla, which is commonly seen in members of the Fabaceae family (like peas and beans), the structure consists of five petals, where:
The vexillum is the largest and topmost petal, often called the standard petal. It is the prominent, larger petal that is seen on the upper side.
The wings are two lateral petals, located beside the vexillum.
The carina (also called the keel) is formed by the two lower petals that are fused together, often enclosing the reproductive organs.
So, the standard petal is referred to as vexillum.
Why Other Options Are Incorrect:
Option 1: Pappus – Refers to the modified hairs or bristles on the fruit of some plants like dandelions, not a part of the papilionaceous corolla.
Option 3: Corona – Refers to a structure in some flowers, such as in lilies or daffodils, where it is a ring-like structure that can be in the center of the flower. It’s not the standard petal.
Option 4: Carina – Refers to the keel formed by the fused lower petals in papilionaceous flowers, not the standard petal.
Thus, the correct name for the standard petal in a papilionaceous corolla is vexillum.
Top Questions on The Leaf
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- UPSEE - 2017
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NEET Notification
Concepts Used:
Leaf
A primary function of the leaf is to provide nourishment for a plant. Leaves get this by extracting water from the earth and carbon dioxide from the air with the help of sunshine.
Parts of a leaf
Following are the parts of a leaf:
- The top part of the leaf is the apex or tip that can be round, pointed, and smooth.
- On most leaves, the lamina, or leaf blade, is the broadest part of the leaf.
- A petiole is a leaf that links to the plant stem.
- Stipules, which are little green addendums near the base of the petiole, can also be seen on leaves.
- Most leaves have a midrib that branches out to initiate vascular tissue veins on the sides.
- Margin refers to the leaf's outer border, which varies depending on the plant type.
- At the bottom of the blade, the base is found; it can be flat, heart-shaped, and round.